Beat the eggs, add the carbonated water to them and stir.
Arrange a layer of phyllo pastry sheets in an oven dish, then a layer of feta, layer of sheets and so on until out of ingredients. Pour the mixture over them.
Separately, braise a little oil and pour it into the oven dish.
Bake about 20 min. on the lower element and another 20 min. with both of them on.