→ Mushroom Filling
01 -
1 tablespoon butter
02 -
1 tablespoon olive oil
03 -
8 ounces cremini mushrooms, sliced
04 -
1 small onion, sliced
05 -
1 clove garlic, chopped
06 -
1 teaspoon fresh thyme, chopped
07 -
1/4 cup white wine or broth
08 -
1 tablespoon fresh parsley, chopped
09 -
1/2 teaspoon truffle oil (optional)
→ Sandwich Assembly
10 -
1 cup fontina cheese, shredded
11 -
1/4 cup parmigiano reggiano, grated
12 -
2 tablespoons salted butter, room temperature
13 -
4 slices bread