Ingredients:
8 slices sourdough or white bread
1/4 cup mayonnaise
1 1/2 cups grated mozzarella
1 1/2 cups grated Gruyère
1/2 cup grated aged goat cheese (such as Midnight Moon from Cypress Grove Chevre)
3/4 cup Bread-and-Butter Pickles
3 ounces thinly sliced prosciutto
6 tablespoons (3/4 stick) unsalted butter
Directions:
Smear both sides of bread slices with mayonnaise. Combine cheeses in a bowl. Sprinkle 4 slices bread with half of cheese mixture, dividing equally. Top each with 3-4 pickles. Divide prosciutto among sandwiches; top with remaining cheese. Cover with remaining bread.
Melt 2 tablespoons butter in each of 2 large heavy skillets over medium-low heat. Add 2 sandwiches to each skillet and cook until bread is golden, 9-10 minutes. Add 1 tablespoon butter to each skillet, flip sandwiches, and cook until bread is golden and cheese is melted, 9-10 minutes longer.