Mashed-potato cakes

4 cups cold mashed potatoes
1/4 onion, grated
1 egg, lightly beaten
1/4 cup flour
Salt and pepper, to taste
Extra flour (for shaping)
Butter or olive oil (for frying)
In a bowl, mix together the mashed potatoes, onion, egg, flour, salt, and pepper. Using floured hands, form the mixture into 4 large cakes.

In a large nonstick skillet, melt the butter or heat the oil. Brown the cakes in the hot fat for about 5 minutes on a side or until they are crisp, golden, and hot in the center.
SERVES 4