How to Make It
Preheat oven to 425°.
Wrap each fish fillet with 1 slice of prosciutto.
Heat a large, heavy, ovenproof skillet over medium-high heat until very hot. Add oil to pan; swirl to coat. Add fish to pan, top side down; cook 2 to 3 minutes or until prosciutto is lightly browned. Turn fish; cook 30 seconds. Transfer skillet to oven; bake at 425° for 5 minutes or until fish is done.
Melt butter in a small skillet over medium heat; cook 2 minutes or until butter begins to brown, swirling occasionally. Add sage leaves to pan, and remove pan from heat. Stir in sherry, kosher salt, and black pepper. Arrange fish on serving plates; spoon sage and butter mixture over fish. Serve immediately.