Line a muffin tin with paper liners, drain the mandarins in a colander and preheat the oven to 180 degrees.
Mix the softened butter with the powdered sugar until creamy. Then stir in the egg until everything is well connected. Mix the flour with the baking powder and stir in together with the egg liqueur. Pour the batter 2/3 full into the molds and cover each muffin with two mandarins. Bake in the oven for about 25 minutes or until they are golden brown in color. Take out and let stand in the tin for a few minutes. Then let cool on a wire rack and dust with a little icing sugar before serving.