INGREDIENTS
2 tbsp
butter, softened, divided
1/4
small sweet onion, thinly sliced
1 tsp
crushed rosemary
1/8 tsp
onion powder
1/8 tsp
garlic powder
salt and ground black pepper
2
thick slices Italian bread
1/4 cup
shredded mozzarella cheese
1
slice sharp American cheese (such as Cooper®)
1
slice provolone cheese