How to Make It
Spray a nonstick pan with cooking spay and heat over medium-high heat.
Spread 1 tablespoon mustard on each of 4 slices of bread, then top each with 2 slices of cheese and 1 slice of tomato. Top with an additional slice of bread.
Place sandwiches in pan, and place another pan on top of the sandwiches.
Cook until bottoms of sandwiches are browned, 2-3 minutes. Flip and continue cooking an additional 2-3 minutes, until bread is golden and cheese is melted.
The CarbLovers Diet