On a floured surface, roll out a full sheet of puff pastry and cut it into quarters.
To each quarter sheet, add a small mound of shredded cheese, then a spoonful of ground beef mixture. The total amount of filling should allow the filling to be fully enclosed in pastry in the next step.
Fold the edges of the puff pastry up and over the filling, pinching it together until the pastry fully encloses the filling. Invert each bomb onto a wire rack.
Brush the top of each bomb with butter and sprinkle with your choice of topping.
Repeat the above assembly instructions with the second sheet of pastry.