1½ pounds ground beef
1 large red onion, peeled and sliced into ¼ inch rounds
2 tablespoons olive oil
2 tablespoons Balsamic vinegar
½ cup mayonnaise
1 bunch chives, sliced thin
1 clove garlic, finely minced
6 ounces blue cheese, crumbled
Salt and black pepper
Sliced tomatoes and baby spinach for garnish
4 Hamburger buns
Coat the sliced red onion with balsamic vinegar and olive oil. Sprinkle with salt and black pepper and marinate for about 1 hour.
Mix the chives, garlic and mayonnaise together and reserve for later use.
Preheat a grill or cast iron griddle pan over medium high heat.
Form the ground beef into 4 to 6-ounce patties about 5 inches in diameter.
Grill the onion slices on the preheated grill for 2-3 minutes per side or until well marked and just tender. Remove onions from the grill and reserve someplace warm.
Season both sides of the hamburger patties with salt and black pepper and lightly coat with olive oil. Place the patties on the preheated grill and cook about 3 minutes per side for medium or until desired temperature. When the burgers are nearly done, distribute the crumbled blue cheese evenly over the 4 patties so the cheese begins to melt. Remove the patties and reserve.
To assemble; spread a liberal amount of the chive aioli over the bottom piece of each bun and add the finished burgers. Garnish with grilled onions, tomatoes and baby spinach as desired.
Loaded and red-wine ready!