1. In a large mixing bowl, combine the butter, sugar and 1 egg yolk. Stir until creamy and combine completely.

2. Add the flour and mix thoroughly. Form the dough into one large ball and wrap it in aluminum foil. Put this in the refrigerator for 30 minutes.

3. Unwrap the chilled dough and, with clean hands, form small balls in the palms of your hand. These are the moon cakes.

4. Make a hole with your thumb gently in the center of each moon cake and fill with about half a teaspoon of your favorite jam or red bean paste. 

5. Brush each cake with the other beaten egg yolk.

6. If you have a mooncale press add flour to it to help ease the cake out after pressing. Then, press each flattened circle in the mold to shape the moon cake. To remove each pressed cake, bang all four sides, until it comes out.# 

7. Preheat the oven to 375 F. (190 C.) degrees. Bake the moon cakes for about 20 minutes or just until the outside edges are slightly brown. Makes about 24 moon cakes. 

# If you don't have a moon cake press, try to shape the cake as round as possible and use a fork or a skewer to draw a design. It can be as simple as making a cross or a series of lines, or more elaborate if you're patient. Another alternative is to press a design from a thoroughly clean stamp (from a craft store), chocolate mold, or similar mold into the top of the rounded cake.

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