Filet Mmmm-onion Burgers

Ingredients:

1 lb. ground sirloin
1 lb. ground chuck, chili grind
1 extra-large red onion
2 T. balsamic vinegar
2 t. salt, divided
2 t. pepper, divided
1/2 c. crumbled blue cheese
1/2 c. crumbled goat cheese
2 T. olive oil
4 oz. button mushrooms, sliced
1/2 c. julienned red bell pepper
2 T. chopped chives
1/4 c. mayonnaise
1/8 t. cayenne pepper
1 T. dijon mustard
6 crusty French rolls

Instructions:

Combine sirloin and chuck in a large bowl. Slice onion into 1 inch slices. Separate out six to eight large rings. Chop remaining onion and divide in halves. Combine one half of chopped onion with meat, balsamic vinegar, 1 tsp. salt, and 1 tsp. pepper. Mix well, and divide into six even pieces. Form each piece into a patty bound by an onion ring. If onions are too small, a larger ring may be pieced together from additional onion, secured with wooden picks. Grill over medium high heat to desired doneness. Combine blue cheese and goat cheese. Set burgers aside, topping with cheese and allowing to melt.

Meanwhile, heat oil in a small skillet. Add reserved onion, mushrooms and bell pepper, and remaining salt and pepper. Cook until onions are translucent. Set aside.

Combine chives, mayonnaise, cayenne pepper and dijon mustard. Set aside.

To assemble burgers, split rolls and warm on grill. Spread both sides of rolls with mayonnaise mixture. Place burgers on bottom of rolls, topping with mushroom mixture, and top of rolls.