Mushroom Lentil Burgers with Quick Pickled Onions and Grainy Mustard Aioli

Lentil, Mushroom + Walnut Burgers with Quick Pickled Onions and Mustard Sunflower Seed Aioli ⎮ happy hearted kitchenLentil, Mushroom + Walnut Burgers with Quick Pickled Onions and Mustard Sunflower Seed Aioli ⎮ happy hearted kitchenLentil, Mushroom + Walnut Burgers with Quick Pickled Onions and Mustard Sunflower Seed Aioli ⎮ happy hearted kitchenLentil, Mushroom + Walnut Burgers with Quick Pickled Onions and Mustard Sunflower Seed Aioli ⎮ happy hearted kitchen

I keep various notebooks and lists on the go of all the recipes that I want to try one day. Most are just titles or ingredients that I think would go particularly nicely together during a certain season or holiday. I would say that the majority of these ideas never actually make it into my kitchen, but I always come back to them when I am in need of a little inspiration.

These burgers have been a long time coming. A year or so ago, back when we were living in France, I was working at a little café making vegetarian ‘plat du jours’ and doing my best to keep hungry skiers happy and healthy. Burgers were on a weekly rotation and I started making different variations of all-time my favorite recipe. I noted this idea down and thought that one day maybe it could make for a nice blog post.

Fast forward to spring in Montreal and here we are. I know things have been a little quiet around happy hearted kitchen lately, and I don’t really have anything to say about it other than the fact that I’ve been a little lazy these days. Yes lazy, but in the absolute best way possible if I can put it that way. Our extended layover here in the city is quickly coming to an end and I am wanting to fill up my days with family and friend time, real time face time with those that matter most. Yes, we are moving once again. And if you’ve been reading along here for a while I can imagine you’re thinking that we never quite stay put, but this one is the big one, the one we’ve been dreaming about for so long, I get butterflies just thinking about it.

So thank you for continuing to come back here, no matter where we are. Just thinking of the past, trying to live in the present + dreaming of the future. It’s a good life.

Now, let’s share a burger.

Lentil, Mushroom + Walnut Burgers with Quick Pickled Onions and Mustard Sunflower Seed Aioli ⎮ happy hearted kitchenLentil, Mushroom + Walnut Burgers with Quick Pickled Onions and Mustard Sunflower Seed Aioli ⎮ happy hearted kitchenLentil, Mushroom + Walnut Burgers with Quick Pickled Onions and Mustard Sunflower Seed Aioli ⎮ happy hearted kitchenLentil, Mushroom + Walnut Burgers with Quick Pickled Onions and Mustard Sunflower Seed Aioli ⎮ happy hearted kitchen


A vegetarian burger that everyone can get into. I encourage you to go all out and make all three components here, the combination is really a winning one. I added some rocket, sliced radishes and chives as extra toppings for some spring flavors, but I will leave the final touches up to you. Dreaming of the days when burgers can be enjoyed out in the sun, oh won’t that be nice. Happiest Spring! x

Makes 6 burgers. Vegan + Gluten Free.



14oz/5 cups/400g mixed mushrooms (I used a mix of button and portobello) cleaned, woody stems removed and thinly sliced
1-2 tablespoon extra virgin olive oil
3 cloves garlic, minced
2 1/2 tablespoon tamari (gluten free, organic if possible)
2 tablespoons apple cider vinegar
1 cup walnuts
2 tablespoons flax seeds
1/3 cup rolled oats (certified gluten free is necessary)
1 cup cooked green De Puy lentils
1/4 cup flat leaf parsley


1 medium red onion, very thinly sliced
1/3 cup apple cider vinegar
1/2 cup water
2 tablespoons maple syrup

Grainy Mustard Aioli

1/2 cup raw sunflower seeds, soaked overnight
1 tablespoon apple cider vinegar
5 tablespoons olive oil
1 tablespoon grainy mustard
1/2 teaspoon fine grain sea salt
2 tablespoon water, or more as needed

Toasted buns, radishes, chives and greens for garnish.



Add olive oil to a large nonstick skillet over medium heat. Add mushrooms and garlic and cook down until soft and tender and reduced significantly in size, about 12-15 minutes. Stir in apple cider vinegar and tamari and cook for another minute or two, scraping any sticky bits on the bottom of the pan and coating the mushrooms. Remove from heat and set aside.

Add walnuts, flax seeds and oats to the bowl of a food processor and pulse until finely ground, then transfer into a large mixing bowl. Add cooked mushrooms, lentils and parsley to the bowl of the food processor and pulse until combined, breaking up any large bits of mushrooms or lentils. Add mushroom lentil mixture to dry mixture and fold to combine. Press mixture into the bottom of the bowl gently with the palm of your hand and place in the fridge to set for at least 30 minutes, or overnight.

Preheat oven to 400 F / 200 C and line a rimmed baking sheet with parchment. Separate burger mix into 6 equal parts and shape into patties. Place on parchment and brush the tops with olive oil. Bake into the oven for 10-12 minutes, then flip and brush the opposite side with oil. Return to oven and bake for another 10 minutes, or until crisp and firm. Remove and let cool slightly before serving. Cooked burgers can be kept in the fridge for a few days and reheated for a quick and easy dinner, or frozen for future burger nights.

Quickled Onions

Place vinegar, apple cider and maple syrup in a small sauce pot and bring to a boil. Remove from heat and add onions. Make sure onions are well covered. Allow onions to ‘quickle’ for at least 30 minutes or overnight. Keep in the fridge in a sealed jar for up to one week.

Grainy Mustard Aioli

Rinse and drain sunflower seeds. Place seeds, apple cider vinegar, olive oil, mustard, and salt into bowl of a food processor and blend until smooth, scraping down the edges and adding water as needed to help thin. Depending on the power of your blender this can take up to 10 minutes for an ultimate smooth consistency. Keep aioli in a sealed contained in the fridge for a few days.

Assemble the burgers!

I made some homemade ‘foccacia’ style buns by following this recipe. I ended up adding a little extra flour in order to get the dough to hold into buns, but otherwise it worked perfectly!

Toast buns. Place warm burger on the bottom bun, pile high with pickled onions, sliced radishes, greens, chives and cracked black pepper. Slather on aioli and dig in. Recommended – roasted potato wedges and a spring green salad to serve.


Let me in on your kitchen creations – tag your photos #happyheartedkitchen and share the love!


  • Reply
    Shelley Ludman
    March 29, 2016 at 1:14 pm

    What a dreamy little burger Jode, and so happy to have you back in this space :) I’m going to do my very best to soak up as much time with you as I can before you head west. I can feel myself getting weepy already… xx

    • Reply
      Jodi Kay
      April 1, 2016 at 2:29 pm

      Thank you, Shelley! Doing this whole thing wouldn’t be the same without you :) xx

  • Reply
    Sus Davy
    March 29, 2016 at 2:38 pm

    And boom! Jodi’s back! These burgers are everything, I’m sat here at my desk counting the minutes until I can make these. Enjoy your last moments in Montreal, I cannot WAIT to hear all about your West coast adventures. Big love to you miss xx

    • Reply
      Jodi Kay
      April 1, 2016 at 2:30 pm

      Sus! Happy Spring! Haha I know it had been a little while, this burger post was just sitting there waiting to be shared! Hope you guys are happy + well! Love xx

  • Reply
    Warm Vanilla Sugar
    March 29, 2016 at 3:25 pm

    The walnuts in here are a great addition! Love the simplicity of these burgers and yet that mustard sure sounds like it packs a punch. Totally trying these!

    • Reply
      Jodi Kay
      April 1, 2016 at 2:31 pm

      Thank you, Katrina! I do love a good mustard sauce and the packs add a nice crunch :) Hope you’re well! x

  • Reply
    Sophie | The Green Life
    March 30, 2016 at 1:05 am

    Ooh you’re moving to the West Coast! This is so exciting!! It’s such a beautiful part of the country. I barely know you, but I’m so happy for you Jodi! I hope you make the most of your last Montreal moments. I can’t wait to keep following your adventures and hearing more about this exciting new chapter of your life. And this burger sounds really dreamy too. That mustard aioli is calling my name. xo

    • Reply
      Jodi Kay
      April 1, 2016 at 2:33 pm

      Thank you, Sophie! That is so sweet! Yes indeed we are moving, to Revelstoke, BC – those mountains are calling! I just love this whole community, it’s always a pleasure reading your post and I find so much inspiration from you :) All about a creamy mustard sauce. Thank you again for the kind words x

  • Reply
    danielle is rooting the sun
    March 30, 2016 at 2:02 am

    lentil and walnut all day jodi, i love this combination. – and mad love for your move and happiness. the realization of dreams in life is never short of inspiring. dreaming and living and making really is the good life, it keeps the mind fresh. happiest spring to you, so happy it’s finally here. xo

    • Reply
      Jodi Kay
      April 1, 2016 at 2:35 pm

      It’s a beautfiul combo, isnt it! Love that note about keeping the mind fresh – especially this time of year! Hope you are enjoying time in your garden, Danielle – thank you for saying hi! xx

  • Reply
    genevieve @ gratitude and gree
    March 30, 2016 at 4:19 pm

    Oh I can’t wait to hear about what’s next for you and Matt! The future is a bit up in the air for us too and it makes me feel better reading your words on just living in the present and dreaming of the future <3

    • Reply
      Jodi Kay
      April 1, 2016 at 2:36 pm

      Yes, Gen! I always have trouble living in the present but it’s so important isn’t it? I’m sure whatever is on the horizon for you guys will work out great, it’s an exciting time! Enjoy it x

  • Reply
    Jessie Snyder | Faring Well
    April 1, 2016 at 11:18 pm

    Yay for moving west!! I’m so incredibly happy for you two Jodi, and cannot wait to see what this move has in store for you! Ecstatic to follow along. And selfishly happy we will be on the same side of the continent, only increasing our odds of hanging one day ;) – xoxo

    • Reply
      Jodi Kay
      April 7, 2016 at 2:31 pm

      YES! Yes to moving and hell yes to following your dreams! West coast living here we come! So many high fives xx

  • Reply
    Raphaelle Cavanagh
    April 9, 2016 at 1:04 pm

    yeaaaa!!! So excited for you two! loads of love to you both Xxx

    • Reply
      Jodi Kay
      May 2, 2016 at 6:00 am

      Made it! Love to you too Raphi xx

  • Reply
    Nicole Spiridakis
    May 1, 2016 at 10:40 am

    I have to come back and comment that these are the best veggie burgers I’ve ever made — or eaten! They are just perfect and I’ve already made them twice over, freezing extras for quick burger nights (perfect). I like them especially with loads of avocado on top and baked sweet potato fries alongside. THANK YOU. Best of luck with your move!

    • Reply
      Jodi Kay
      May 2, 2016 at 6:00 am

      NICOLE! Thank you so very much! Your comment just made my day (week?)! I love these burgers too and I am so pleased you enjoyed them at home. Love the addition of avocado. So grateful for you taking the time to come back here :) Take care x

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