Divide the toast into triangles. In a casserole dish or large bowl, mix the milk with 1 teaspoon powdered sugar, 1 teaspoon cinnamon and the vanilla flavor well to create a little foam.
Place the toast in the milk mix, turn after about 1/2 minute so that it is well saturated on both sides.
Heat some clarified butter in a pan and place the toast slices in it. Fry until golden brown on both sides and dust with a little cinnamon again. To serve, dust with powdered sugar and drizzle with maple syrup.