Combine first 6 ingredients in a medium bowl; stir in 1/4 teaspoon salt.
Heat a large nonstick skillet over medium-high heat. Coat pan with cooking spray. Combine remaining 1/4 teaspoon salt, chili powder, and black pepper, stirring well; sprinkle evenly over fish. Add fish to pan, skin side up; cook 4 minutes on each side or until fish flakes easily when tested with a fork or until desired degree of doneness. Serve with pineapple mixture.