Bake at 400 degrees. Bake 12 muffins in a muffin pan. Spray 10 cups with cooking liquid. Set aside.
On medium-high heat in a large skillet, brown the ground beef. Drain.
Mix together the mustard, Worcestershire sauce and brown sugar. Mix together. Turn heat to LOW, then let it simmer as you prepare the muffins.
Take one biscuit and smush to form a large circle shape. This is the easiest method I have found, although you could also use a rolling board.
You can then press it into a muffin tray. Continue to make more biscuits.
In each biscuit cup, add 2 cubes Velveeta.
You can top each biscuit with a generous scoop of cheeseburger mixture.
Cook for 13-15mins, or until biscuit cups are golden on top and cooked through.