Grind pepper over fish and wrap each piece in 2 slices of prosciutto.
Spray a large nonstick skillet with cooking spray. Heat to medium-high heat. Add fish fillets and cook for 3-4 minutes per side, until prosciutto is crisping and fish is starting to brown. You may need to turn the heat down to medium after a few minutes. Note: adjust cooking time if using another type of fish that is thicker than tilapia.