White Pizza Grilled Cheese

2 tablespoons butter, softened, divided 1/4 small sweet onion, thinly sliced
Onions Sweet
1 lb for $0.99 - expires in 2 days

1 teaspoon crushed rosemary 1/8 teaspoon onion powder 1/8 teaspoon garlic powder salt and ground black pepper to taste 2 thick slices Italian bread 1/4 cup shredded mozzarella cheese 1 slice sharp American cheese (such as Cooper®) 1 slice provolone cheese

Melt butter in a nonstick skillet over medium heat. Cook and stir onion until starting to brown, about 5 minutes. Transfer to a plate.
Mix remaining 1 tablespoon butter, rosemary, onion powder, garlic powder, salt, and pepper in a small bowl. Spread on one side of each slice of bread.
Place 1 slice of bread buttered-side down in the skillet. Top with onion, mozzarella cheese, American cheese, and provolone cheese. Cover with second slice of bread, buttered-side up. Cook until golden brown, about 3 minutes. Flip with a spatula; cook until second side is browned and cheeses are melted, about 3 minutes more.