Portobello Mushroom Burgers

This recipe you have to marinade the mushrooms for at least half an hour. I marinaded it longer because why not have extra flavor? I was pleasantly surprised at how well these tasted. I would honestly just eat the mushroom by itself and be fine with it.

2-4 Portobello Mushroom Caps (just depends on the size of the caps)
2 Tbsp Balsamic Vinegar
1 Tbsp Soy Sauce
1 Tbsp Olive Oil
1 Tbsp Chopped Rosemary (I did not have this so I didn't put it in.)
1 1/2 tsp Steak Seasoning (I used Montreal Steak Seasoning)

For the burger
Slices of red onion
Swiss cheese for each mushroom
Slices of tomato
Slices of avocado
Spinach (I also did not do this)
Buns (Or if you want to be extra healthy you can do it in a leaf of lettuce?)

In a large bowl or tupperware mix together the marinade, vinegar, soy sauce, oil, rosemary, and steak seasoning. Put in the mushroom caps. (I put mine in tupperware that way I could shake the marinade around the mushrooms every once in a while.) Toss with sauce and turn a few times. (Marinade 20-30 minutes at room temperature.)

Heat the grill. When hot add the mushrooms on the grill and keep the marinade for basting. Grill on each side for about 7 minutes or until tender. Brush the marinade on frequently. A minute before taking them off, add the swiss cheese to each mushroom and let it melt.  We also toasted our buns on the grill. A little bit of butter or mayo on the bun and then put them on the grill. Assemble your burger once your mushroom is cooked with bun, tomatoes, onion, avocado, and spinach.