1Preheat your grill or skillet over medium-high heat.
Place the 8 pattys on the grill or skillet and cook for about 3-4 minutes on each side, or until they reach your desired level of doneness.
During the last minute of cooking, place a slice of cheese on each patty to melt.
While the patties are cooking, slice the buns in half and lightly toast them on the grill or in a toaster.
Once the patties are cooked and the cheese is melted, assemble the burgers by placing one patty with cheese on the bottom half of each bun.
Add a second patty with cheese on top of the first one.
Spread 1 tablespoon of ketchup on the top half of each bun.
Place the top half of the bun on the assembled patties.
Serve the double cheeseburgers immediately and enjoy!