How to Make It
Preheat oven to 375°F.
Melt butter in a small saucepan over medium-high. Add sage and garlic. Reduce heat to medium; cook 5 minutes or until butter is foamy and just starting to brown, swirling pan occasionally. Place sage leaves on a paper towel-lined plate. Discard garlic. Reserve butter.
Place 2 potato slices in the bottom of each of 12 muffin cups coated with cooking spray. Sprinkle evenly with 1/2 teaspoon salt and 1 tablespoon Parmesan. Add 2 potato slices to each cup; top each with 1/2 teaspoon browned butter. Cover with foil; bake at 375°F for 25 minutes or until tender. Remove pan from oven; discard foil. Drizzle remaining browned butter evenly over potatoes; top evenly with remaining 3/4 teaspoon salt and remaining 3 tablespoons cheese.
Preheat broiler to high.
Broil potatoes 3 minutes or until cheese melts. Remove pan from oven; cool. Place potato stacks on a platter; top with reserved sage leaves.