At home: Put cornmeal, flour, salt, and pepper in a 1-gallon zip-lock plastic food bag. Pack bacon drippings in a small, widemouthed Nalgene jar (see notes). Transport in an insulated chest.
In camp: Gut fish. If desired, or for fit in pan, cut off heads and tails. Rinse fish well.
Put fish in the plastic bag with the cornmeal mixture and shake to coat.
Put bacon drippings in a nonstick 10- to 12-inch frying pan over medium heat. When hot, add fish to pan without crowding. Brown well and cook just until thickest part flakes easily when prodded to the bone, about 5 minutes per side, depending on size. If desired, serve bacon with fish.