Cook the barley in a saucepan filled with boiling water for about 25 minutes or until it is tender. Let cool down.
Apply a fine coat of oil onto eight cups in a muffin pan.
In a bowl, mix all ingredients (but only half the cheese).
Distribute this mixture among the muffin cups, then also distribute the remaining cheese on top of each mixture-filled cup. Bake in the oven 25 to 30 minutes or until the mini-cakes are cooked and gratinated.