In a large bowl, combine the ground beef, salt and pepper. Divide the mixture into four equal-sized balls (they should be 4 oz each). One at a time flatten the ball to 1/4 inch thickness. Place one (1/2 oz) slice of blue cheese in the center and fold the ground beef in around it, like a package. Seal the edges, shape into a patty and press your thumb into the center. Repeat for the remaining three patties.