Well, that’s a mouthful.
I was originally going to grill portabellas filled with a kasha pilaf mixture, but I wasn’t in the mood for something grainy like that. I wish I had a better explanation for how these flavors came together, but I just brainstormed about what I had in the pantry and the refrigerator and what would be vaguely Italian. I love thinly sliced, gently charred grilled zucchini (and had lots in the refrigerator!) and had provolone cheese. How about some protein and fiber? White beans mashed into a spread with garlic, rosemary, olive oil, and Parmesan.
I made a light spread for the buns as well (onion burger buns from Publix) with mayo, red wine vinegar, garlic, and a sprinkle of herbs from Penzey's.
These were huge and delicious with the combination of flavors from the grill and the fresh garlic. No need for anything on the side, either, with all the veggies and protein in one sandwich!
As an aside, if you don’t feel like dragging out the grill or if it’s too cold, you can also make this in a broiler, but you’ll be missing out on the wonderful grill flavor.
Balsamic Grilled Portabellas Topped with Rosemary White Bean Mash and Grilled Chopped Zucchini
4 large portabella caps
2 medium zucchini
1/4 cup balsamic vinegar
1/4 cup olive oil plus 1 tbsp, divided
1 tsp dried thyme
1 cup cannellini beans, rinsed
3 tbsp shredded Parmesan, divided
2 tsp chopped dried rosemary (or 1 tbsp chopped fresh)
3 cloves of garlic, minced, divided
1/4 cup mayonnaise
1 tbsp Dijon mustard
1 tbsp dried mixed herbs (or 2 tbsp fresh)
2 tsp red wine vinegar
4 slices of provolone cheese
Onion sandwich buns
Salt and pepper
Wash the portabella mushrooms and zucchini. Scrape the gills from underneath the mushrooms as they can make the mushrooms taste bitter. Slice the zucchini into four slices lengthwise. Mix the balsamic vinegar, olive oil, thyme, and salt and pepper to taste in a bowl or storage container and add the vegetables. Set aside to marinate for at least one hour.
Prepare the grill or broiler.
While the grill or broiler is heating, mash the cannellini beans with 1 tbsp olive oil, 2 tbsp of the Parmesan, the dried rosemary, and 2 cloves of garlic. Add salt and pepper to taste. Warm the mixture briefly on the stovetop or in the microwave.
Combine the mayonnaise, Dijon mustard, herbs, red wine vinegar, and remaining Parmesan and garlic. Add salt and pepper to taste.
When the grill is ready, brush the grates with additional olive oil and grill the vegetables until done to your liking. I prefer mine with a little char! Keep an eye on the zucchini because it can go from raw to burnt in a second.
When the vegetables are ready, remove from the grill. (If you like grilled buns for your sandwiches, this is a perfect time to grill them.) Chop the zucchini slices.
To assemble the sandwiches, spread the top and bottom buns with the herb garlic mayonnaise, place a mushroom on the bottom bun, 1/4 of the bean spread, 1/4 of the chopped zucchini, and the provolone cheese.
The vegetable stack can be stored overnight for lunch the next day, and can also be served without the bun or herb garlic mayonnaise.