Where’s the beef? You don’t need it when you make these amazing vegetarian mushroom burgers! The patty is made of mushrooms, and when topped with caramelized onions and a garlic aioli, it’s burger heaven!!!
If you want to encourage someone to eat vegetables, start with mushrooms. At least, this was the case with the Godfather. He wasn’t a big vegetable eater when we started dating, so as we got serious, I needed to expand his palate a bit in that department. One of the easiest ways to do that was to start cooking with mushrooms. He already enjoyed mushroom Swiss burgers, so I knew mushrooms were a good place to start. I started putting them into stir fry and pasta dishes, and they’re a regular item in our crisper. Nevertheless, you can imagine my surprise when my husband, who makes an ah-mazing beef burger (recipe posting in the next few weeks), came to me one day and said, “I’d like to make a burger with a mushroom patty. Not just a portobello mushroom cap with burger toppings, but an actual patty made out of mushrooms.” I was of course, curious, and totally excited, and that’s how these vegetarian mushroom burgers came to be. It took exactly 1 bite for them to earn a place on our “favorite burger list.”
I wish I could better describe how amazing these burgers are. Actually, I really wish I could just reach through the screen and hand you a burger to try, because that would mean I’d have one to eat too. I can’t even look at these pictures without smelling the patties and tasting the best vegetarian burger I have *ever* eaten.
The Godfather was able to make these up rather quickly using our big food processor so he didn’t have to dice the mushrooms by hand (what a chore!), and then he cooked them down in a large skillet to reduce the liquid. This is an important step, because mushrooms retain a lot of liquid and if you don’t cook them down before shaping the patties, your patties won’t hold together and you won’t get the right “burger” texture.
After cooking down the mushrooms he mixed up the patties, and cooked them right on our grill pan. He only cooked half because the smell made our mouths water and we felt ravenous, but they grilled up so well on the grill pan. We enjoyed the rest the next day, and they grilled up even better than the first day! So if you’re going to make these vegetarian mushroom burgers for a summer barbecue if you have vegetarian guests (even if you don’t, seriously, make them), you can make the patties the day before and refrigerate. We haven’t tested on the grill yet, but the Godfather is confident that the patties would hold up on the grill. We fully intend to outdoor grill some mushroom patties this summer.
Summer is just around the corner, as is grilling season for everyone that isn’t crazy enough to be grilling/barbecuing in the snow (*cough* the Godfather), so my advice to you is to get to the store to buy some mushrooms and start “practicing” now. You’ll be amazed at the incredible texture and flavor you get from these mushroom burgers, and it will never once cross your mind to ask, “Where’s the beef?”
Vegetarian Mushroom Burgers
Mushroom Burger Patties:
- 24 oz fresh mushrooms
- 1 tbsp oil
- 7 cloves garlic minced
- 1/2 cup medium onion about 1, finely diced
- 1 tsp salt
- 1/2 tsp black pepper
- 1/2 tsp dried oregano
- 2/3 cup rolled oats
- 3/4 cup panko bread crumbs
- 1/2 cup Parmesan cheese grated
- 2 eggs lightly beaten
- 6 cloves roasted garlic or 4 cloves finely minced fresh, diced fine
- 1/4 tsp salt
- 1/2 cup mayonnaise
- tbsp juice from half a lemon about 1
To assemble the burgers
- 6 hamburger buns
- 6 slices Swiss cheese
- 1 cup caramelized onions
- Wash mushrooms and pat dry
- Run mushrooms through food processor, chop 5-10 seconds or until cut into small chunks
- Cook chopped mushrooms in large skillet with oil until juice is released and mostly evaporated
- In large mixing bowl, place cooked mushrooms and mix in minced garlic, chopped onion, salt, black pepper, oregano, rolled oats, panko, and parmesan cheese
- Add beaten eggs to the bowl, stir and mix until consistent
- Let mixture stand for up to 10 minutes
- Form into 1/4 to 1/3-pound patties (no larger than the size of the palm of your hand)
- Cook patties on grill pan or conventional grill; do not flip until patty can be easily moved with spatula
Making the easy garlic aioli:
- Combine all ingredients in a small bowl, cover, and place in the refrigerator until ready to use
When it's time to serve the burgers:
- Place one patty per bun and top with cheese, onions, and garlic aioli.