- In a medium bowl, combine 1/2 cup butter and cream cheese. Beat with an electric mixer on medium to high speed for 30 seconds. Add 3 tablespoons cocoa powder and sugar. Beat until combined, scraping bowl occasionally. Beat in as much of the flour as you can with the mixer. Using a wooden spoon, stir in any remaining flour (mixture will be crumbly). Form mixture into a ball. Cover and chill for 1 hour.
- Preheat oven to 375 degrees F. For pastry shells, divide dough into 24 pieces; shape each piece into a ball. Press a ball evenly onto the bottom and up the sides of each of the 24 ungreased 1 3/4-inch muffin cups. Gently prick dough with a fork. Bake in the preheated oven for 6 to 8 minutes or until pastry shells are set and dry (shells will puff during baking). Cool in muffin cups on wire racks for 5 minutes. Gently remove from cups; cool completely on racks.
- For fillings, in a large bowl, combine peanut butter, 1/3 cup butter, and vanilla. Beat on medium speed for 30 seconds. Gradually beat in powdered sugar. Beat in enough of the milk to make a mixture of piping consistency.
- Divide peanut butter mixture in half and place in separate bowls. Add 2 tablespoons cocoa powder to one portion; beat until combined. If necessary, beat in additional milk to make the cocoa mixture piping consistency.
- In a large decorating bag fitted with a star tip, spread the cocoa filling down one half of the bag. Spread the peanut butter filling down the other half of the bag. Pipe swirls of the fillings into pastry shells. Makes 24 tassies.
From the Test Kitchen
Place tassies in a single layer in an airtight container; cover. Store in the refrigerator for up to 3 days or freeze for up to 3 months.