1 tablespoon butter
1 tablespoon olive oil
8 ounces cremini mushrooms, sliced
1 small onion, sliced
1 clove garlic, chopped
1 teaspoon thyme, chopped
1/4 cup white wine (or broth)
salt and pepper to taste
1 tablespoon parsley, chopped
1/2 teaspoon truffle oil (optional)
1 cup fontina cheese (or gruyere, or mozzarella), shredded, room temperature
1/4 cup parmigiano reggiano (parmesan cheese), grated
2 tablespoons salted butter, room temperature
4 slices bread (gluten-free for gluten-free)
- Melt the butter and heat the oil in a pan over medium heat, add the mushrooms and onion and cook until until they start to caramelized and turn golden brown, about 10-15 minutes.
- Add the garlic and thyme and cook until fragrant, about a minute.
- Add the wine, deglaze the pan and cook until most of the liquid has evaporated, about 2-3 minutes.
- Season with salt and pepper, add the parsley and remove from heat and let cool a bit.
- Mix the cheese into the mushrooms.
- Butter one side of each slice of bread and place 2 in the pan buttered side down.
- Top each with 1/2 of the mushroom mixture and finally the remaining slices of bread with the buttered side up.
- Grill in a pan, preheated over medium heat, until golden brown on both sides and the cheese has melted, about 2-4 minutes per side.