Portobello Steaks with Lemon Basil Aioli

Posted by Planet Bake on Nov 18th 2021

Portobello Steaks with Lemon Basil Aioli


The most challenging things about trying to eat a healthy diet is all of the conflicting information out there. Some research shows that butter and eggs cause heart disease while others claim that the benefits might outweigh the risks. Or that the fiber in whole grains is the key to weight loss and hormone regulation while others portray grains as the modern day devil. At the end of the day it’s all so confusing that it can be hard to decide what’s truly best for our health. Of all the research available to us, one thing I’ve never seen controversy over is the benefit of eating more fruits and vegetables. There is no denying that plants are the most nutrient-dense and sustainable foods we can feed ourselves.

But even in the realm of plant-based diets, there is confusion about what’s best. Should I only eat fruit? Is it okay to eat oils? Am I killing off the nutrients if I cook my food? How many macros should I eat with each meal?

I don’t know about you, but all of that jazz makes my head start to spin. Thinking about what to eat on that deep of a level is overwhelming. It’s enough to make me hate food!

I LOVE food. I love healthy food that makes me feel energized and happy.

I know portobello mushrooms aren’t everyone’s favorite but I feel like there’s a strong chance they just haven’t had it prepared the right way. With a simple marinade they can transform in tender, juicy steaks that are packed full of flavor.

I served them with a simple pesto aioli using plant-based mayo, garlic, lemon and basil. If mayo isn’t your thing, feel free to substitute half of an avocado or plain yogurt instead.


  • 4 large portobello caps
  • 4 tablespoons balsamic vinegar
  • 3 tablespoons avocado oil or virgin olive oil
  • 1 tablespoon tamari (or soy sauce)
  • 1/2 teaspoon dried oregano
  • 3/4 cup plant-based mayo (or plain yogurt or 1 small avocado)
  • 1 teaspoon lemon zest + juice of 1/2 lemon
  • 1/2 cup packed fresh basil leaves
  • 2 garlic cloves
  • salt to taste


1.) Remove the stems from the portobello caps and wipe each one clean with a damp paper towel. Arrange them facing up in a shallow baking dish then set aside.

2.) In a small bowl, whisk together the balsamic vinegar, oil, tamari, oregano, and a pinch of salt & pepper. Pour the marinade on each of the mushroom caps and use your fingers to spread it out to the sides and bottom. Allow to sit for about 10 minutes.

3.) Meanwhile make the aioli by combining the mayo, lemon zest and juice, basil and garlic in a blender. Blend on high until smooth. Add one to teaspoons of water if needed to thin. Taste test and add salt as desired.

4.) Lightly grease a grill pan or cast iron skillet then warm over medium heat. Add the mushroom caps and cook for 5-7 minutes on each side, until tender. Serve warm with basil aioli and enjoy!