1lbItalian sausage, removed from the casing (see notes)
1clovegarlic, very finely chopped
4tablespoonsmayonnaise, divided (see notes)
1tablespoonfresh basil, chopped
2tablespoonsgrated parmesan cheese
Salt and freshly ground black pepper
3tablespoonsolive oil, divided
1/2medium red bell pepper, cut into thin strips
1/2medium sweet onion, sliced
8thick slices Italian bread
6ouncesfresh mozzarella, coarsely shredded
Add the sausage, garlic, vinegar, 1 tablespoon of the mayonnaise, panko crumbs, basil, parmesan cheese and a few grinds of black pepper (no salt) to a large bowl. Using your hands, combine gently, but thoroughly. Form into 4 thin, equal-sized patties, transfer to a plate and chill for 15 minutes.
While the burgers chill, heat 1 tablespoon of the olive oil in a heavy skillet over medium heat. Add the bell pepper and onion, season lightly with salt and pepper and cook until the onion is translucent and the peppers have softened, 3 to 4 minutes. Transfer to a bowl and set aside.
In the same pan, heat the remaining 2 tablespoons of olive oil over medium-high heat. Add the burgers and cook until no longer pink in the middle, about 4 minutes per side. Transfer the burgers to a plate and wipe out the pan.
Preheat the oven to 250°F.
Using about half of the grated mozzarella, scatter a portion on top of 4 slices of bread. Add a tomato slice to each, top with a burger, a portion of the pepper-onion mixture, and finish with the balance of the mozzarella. Add the second slice of bread.
Coat the top of each sandwich with some of the remaining mayonnaise. Heat the pan over medium heat and add two of the sandwiches, mayo side down. Cook until lightly toasted (2 to 3 minutes), compressing the sandwiches slightly with the back of a spatula as they cook. Coat the top slice of bread with mayonnaise, flip the sandwiches and continue cooking until the cheese is melted and the bread is toasted, about 3 minutes longer.
Place the finished sandwiches on a baking sheet and transfer to the oven to keep warm. Cook the remaining two sandwiches in the same manner. Alternately, you can use 2 pans and cook all 4 sandwiches simultaneously. Serve immediately.
Tips for Making This Recipe
You can use any variety of Italian sausage - pork, chicken or turkey. Our favorite is chicken sausage because of its lighter, tender texture.Keep in mind that because you're starting with a meat product that's already been seasoned, you need very little salt in this recipe - just a little on the sautéed onions and peppers.
Why use mayonnaise instead of butter?
The exterior of the bread for these sandwiches is coated with mayonnaise to give them a golden, toasty exterior without the added richness of butter. We prefer this for a lot of grilled sandwiches - it's easier to work with and really does a great job toasting the bread.