1. Mashed potatoes cooked with a fork, season with a pinch of salt and pepper.
2. Take potato wedges (about the size of an ice cream scoop), flatten them between the palms of your hands and place a piece of cheese and ham in the middle. Bring all the edges together, then roll into a ball.

3. Melt the butter and add four.

Cook for 30 seconds.
Start pouring in the milk little by little, whisking constantly to avoid lumps forming.
4. Cook the sauce for about 10 minutes, whisking constantly, or until thick and bubbly.

Season with salt, pepper and nutmeg to taste.
5. Place the potato balls on a baking sheet and pour the sauce over them. Add the grated cheese and bake in the oven at 180C/350F for 20 minutes.