Break dough into 12, fist-sized blobs.
Flatten each ball between your hands to about 4 inches in diameter.
Place about ¼ cup of beef mixture on center of each piece of dough, and fold up edges and pinch together to seal.
Leaving the buns in the oven, turn the temperature up to 350 degrees.
Bake until lightly browned. Remove from oven, lightly butter tops of buns.