Preheat the oven to 400 degrees F. Line a baking sheet with parchment paper. In a large saucepan, combine the milk, butter, salt, and black pepper over medium-high heat. Bring to a boil, then remove from the heat, add the flour, and with a wooden spoon, stir briskly for about 1 minute to incorporate. Return to the heat and continue stirring for 1 minute, over medium-high heat. Remove from the heat and add the eggs one at a time, beating after each addition. Add the cheese and ham and beat until it is incorporated and a slightly soft dough forms. Drop the dough by the spoonful onto the prepared baking sheet to form a ring (about 12 to 14 spoonfuls. Bake for 10 minutes, then reduce the oven temperature to 350 degrees F. and bake until golden brown, about 25 minutes. Remove from the oven and serve warm on a platter.