Heat the stock to a simmer and then whisk in the cornmeal.
Whisk butter, salt, and pepper into the cornmeal mixture. Set aside to cool. When cool enough to touch, roll into balls about the size of a golf ball.
Poke a hole in the middle and fill with 1/4 teaspoon each of the ricotta and ham and roll up.
In a deep saucepan, heat 4 inches oil to 375 degrees F.Fry for 2 to 3 minutes in hot oil. Drain on paper towels and serve.