Scandanavian Butter Burgers with Lingonberry Mustard
12 slices hearty rye bread with caraway seeds
2 tablespoons softened butter
6 tablespoons lingonberry jam
3 tablespoons whole grain mustard
1 pound ground chuck
½ pound ground lamb
½ pound ground veal
¼ cup grated sweet onion
2 tablespoons chopped fresh dill
1 stick frozen butter
½ teaspoon salt
Vegetable oil for grill
1 tablespoon butter
1 teaspoon olive oil
½ teaspoon salt
6 cups thinly sliced sweet onion (about 2 large)
12 slices havarti cheese
Preheat a gas or charcoal grill to medium-high heat.
Spread softened butter over 1 side of 12 slices bread; set aside.
Combine lingonberry jam and mustard; set aside.
Combine meats, onion and dill in a large bowl with a fork just until blended.
Grate frozen butter using the largest holes on a box grater and sprinkle over the surface of the meat mixture. Fold butter into meat mixture using hands just until incorporated. Divide mixture into 6 equal portions; shape each into an oval patty roughly the size of the sliced bread. Make a slight depression in the center of each burger. Sprinkle tops of burgers with ½ teaspoon salt. Cover and hold in refrigerator.
Heat 1 tablespoon butter and 1 teaspoon olive oil in a large skillet over medium-high heat. Add onions and ¼ teaspoon salt. Saute 8 minutes or until softened and beginning to turn dark brown on the edges. Remove from heat and keep warm.
Lightly brush the grill rack with vegetable oil. Place the patties on the rack, cover, and cook, turning once, 4 minutes per side for medium. During the last minute of cooking, top each patty with a slice of cheese. Let stand until slightly melted. Remove from grill and keep warm.
Place bread, butter side down, on the the grill and lightly toast. Remove from grill.
To assemble the burgers, place 6 slices bread toasted side down and top with 1 slice cheese each. Top with burgers, cheese side up. Top each burger evenly with lingonberry mustard and sauteed onions. Top with remaining rye bread, toasted sides up. Slice in half and serve. immediately.