Hamburger with Double Cheddar Cheese, Grilled Vidalia Onion and Horseradish Mustard

This is a combination of my brother's and Bobby Flay's hamburgers on the grill. My brother's recipe calls for 1/2 chuck and 1/2 sirloin, which gives it a wonderful flavor and texture. His addition of bacon gives the hamburgers a fantastic taste not even Bobby Flay can match. He serves his hamburgers on English Muffins coated with olive oil and toasted on the grill. You can choose this alternative or regular hamburger rolls.

The cheese and the Vidalia Onions are Bobby Flays and my idea, long before he was a glimmer in his mother's eye! He can take credit for the horseradish mustard!

Yield
8 servings

Ingredients
1 pound freshly ground chuck
1 pound freshly ground sirloin
8 bacon strips
Salt and freshly ground black pepper
8 slices white Cheddar, sliced 1/4-inch thick
8 slices yellow Cheddar, sliced 1/4-inch thick
8 hamburger buns or English Muffins
Horseradish Mustard, recipe follows
8 leaves Romaine Lettuce
Grilled Vidalia Onions, recipe follows
Dill pickles, sliced
Ketchup

Directions

Preheat grill or a cast iron skillet to high.

Combine the sirloin and the chuck

Divide the beef into 8 (4-ounce) burgers. Shape and with your thumb create a dimple in the middle, it helps it cook evenly. Season on both sides with salt and pepper, to taste. Lay a strip of bacon around the hamburgers. Grill or cook in the skillet for 3 to 4 minutes on each side for medium-rare doneness. During last minutes of cooking add 2 slices of cheese to each burger, cover grill and let melt, approximately 1 minute.

Place burger on bun and top with Horseradish Mustard, lettuce, Grilled Vidalia Onions, pickles and ketchup.

Horseradish Mustard:

1/2 cup Dijon mustard
2 tablespoons prepared horseradish, drained
Whisk mustard and horseradish together in a small bowl.

Grilled Vidalia Onions:

2 Vidalia onions, sliced crosswise, 1/4-inch thick slices
2 tablespoons olive oil
Salt and freshly ground black pepper
Brush olive oil on both sides of the onions and season with salt and pepper. Grill the onion slices for 3 to 4 minutes on each side until golden brown.