Northwoods Burger

These are big, messy, and oh so great burgers.  There's a whole lot of flavors which really work well together, especially if you like blue cheese.  The mixture is very moist and you'll want to be careful as you turn them on the grill.   

FOR TOPPING:
1/2 cup sour cream
2 Tbs prepared horseradish
1 tsp spicy brown mustard

FOR BURGERS:
1 1/2 lb. lean ground beef
1 cup cooked rice
1 cup chopped fresh mushrooms
3 tsp chopped fresh tarragon
3 oz crumbled blue cheese
1 tsp salt
1/2 tsp fresh ground black pepper
2 Tbs spicy brown mustard
1/4 cup dark beer 

FOR SERVING:
4 slices sweet onion
4 whole wheat buns
1 small bunch red leaf lettuce

Heat Old Smokey charcoal grill and lightly oil the grill or grill grates.  In a small bowl, mix sour cream. horseradish and teaspoon of mustard.  Set aside.
Mix ground beef with rice, mushrooms, tarragon, blue cheese, salt, pepper, mustard and beer.  Form into 4 patties.
Grill patties for 4-6 per side or until done.  Place onion slices on grill for the last few minutes of grilling flipping once.  Add the buns to the grill during the last minute of grilling.
Assemble burger and top with lettuce, grilled onion and the sauce.