Half of the baking foil is greased with vegetable oil.
Put the potatoes and whole garlic cloves on the greased part of the foil, season with salt and pepper.
Put the butter, cut into pieces, on the potatoes. Sprinkle the sliced sausage on top.
Cover with the second half of the foil. Bend at the edges.
Bake in a preheated 180 degree oven for about 40 minutes.