In a shallow bowl, combine flour, spices, and cheese. Dredge fillets in seasoned flour. Saute fillets in a nonstick skillet over medium heat for 8 minutes, turning once to brown both sides. Transfer fish to a warm platter. Microwave spinach while heating spaghetti sauce on the stove. Spoon equal amounts of sauce on 4 plates, top with spinach and lay fish on bed of spinach.
