Adapted from a recipe found online at thatsmyhome.com, these are going on my Christmas trays this year! **12/21/07 Update: I have now made these and have to admit the dough is pretty hard to handle, but the end result is worth it!
Sift together flour, cocoa, baking soda and salt; set aside.
Cream together butter, sugar, vanilla, egg and sour cream.
Stir in dry ingredients.
Cover and refrigerate dough.
To prepare filling: Combine coconut and milk in a pot over medium heat. Combine cornstarch and sugar; stir into milk. Bring to a simmer and cook, stirring constantly until thickened. Remove from heat and set aside to cool.
Preheat the oven to 375 degrees. Grease cookie sheets.
On a floured surface, roll dough to 1/8 inch thickness. Cut into 2-1/2 inch circles. Place half of the circles 1-1/2 inches apart on the cookie sheets. Spoon 1 teaspoon filling into center of each circle. Top with another circle of dough and press edges to seal.
Bake 8 to 10 minutes. Cool cookies on baking sheet 5 minutes then remove to a wire rack to cool completely. Dust with powdered sugar. Store in a single layer.
I had a very hard time with these (sticky dough) and found that using cocoa to roll them out really helped. They are difficult to do, but once you get the hang of it, they go faster and easier. It's all worth it in the end!
I had a lot of filling left over, but I did make them smaller (about 2 1/4 inches) and lost some dough due to mishaps. I would suggest using a heaping teaspoon of filling in each one.