Recipe: Whole30 Paleo Open-faced Portobello Burger

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This one's an oldie, but a goodie!

I've made this Whole30 Paleo Open-faced Portobello Burger recipe several times during my rounds of Whole30, and I'm just getting around to sharing it on here. One of the reasons I love it is that IT IS SO SIMPLE

The blend of flavors and textures is fun, but it is seriously so easy to make and customize. Because of this, it makes a great date night meal - it's the perfect combination of easy and delicious.

Serve this burger up with a side of roasted butternut squash crinkle fries and sautéed broccolini and you've got yourself a five-star dinner!

Recipe: Whole30 Paleo Open-faced Portobello Burger | Happy Healthy Joe

Pro-tip: I love to stock up on a lot of my go-to healthy dry goods and superfoods at Thrive Market! They have a great discounts on a lot of natural living products and my favorite healthy pantry items.


Makes 2 servings.



  1. Preheat your oven to 400 degrees.

  2. Prepare the mushrooms and onions. If your portabello mushrooms have long stems, trim them so they don't stick out too much. Thinly slice the onion into rings. In a glass container, add about 1/4 cup of coconut aminos, 2 tbsp of olive oil, garlic, and salt and pepper. Place the mushrooms and onion slices in the mixture and allow them to soak for 15-20 minutes, making sure to flip so both sides absorb the flavor.

  3. Place the mushrooms and onions in a baking dish and bake for about 25 minutes, flipping halfway through. If you prefer, grilling is always an option as well.

  4. While the mushrooms are marinating, turn on your stovetop or grill and start cooking the burgers. Heat up a pan, add the coconut oil, and throw on the patties when ready. This tutorial from Kitchn will teach you how to make the PERFECT burger. If you're tight on time, Trader Joe's has some great grass-fed angus burger patties in the frozen section.

  5. In a separate pan, fry the eggs. This tutorial will walk you through different ways you can fry your egg - for this recipe, I prefer sunny side up (runny yolks for dayyyys!).

  6. Make the smashed avo. This is honestly as easy as it sounds - in a bowl, place the diced avocado flesh and mash with a fork. Add salt and pepper to taste.

  7. By now, everything should be ready and it's time to plate the burgers! Start off with the portobello mushroom as the base layer. Add the grass-fed beef burger patty. Spread on the smashed avocado, add a dollop of the avocado mayo, layer with a roasted onion, and top with your fried egg. Your Whole30 Paleo Open-faced Portobello Burger is complete!

  8. Dig in!

Recipe: Whole30 Paleo Open-faced Portobello Burger | Happy Healthy Joe