Ingredients

CARAMELIZED ONIONS

4 large (10 cups) sweet onions, sliced 1/4-inch thick

1/4 cup Land O Lakes® Unsalted Butter

2 teaspoons salt

1 cup white wine*

AU JUS DIPPING SAUCE

3 cups low-sodium beef broth

2 cups water

1 cup apple cider vinegar

1 bay leaf

1/2 teaspoon ground thyme

1/2 teaspoon dried parsley flakes

SANDWICH

8 slices thick-cut rosemary boule bread

8 (3/4-ounce) slices Land O Lakes® Deli 4 Cheese Italian Blend

1/4 cup Land O Lakes® Unsalted Butter, softened

Directions 

Melt 1/4 cup butter in large skillet over medium-low heat until sizzling. Add onions and salt; cook, without stirring, 15 minutes. Continue cooking, stirring occasionally, 1 hour or until onions are dark golden brown. 

Increase heat to high. Add wine; cook until liquid has evaporated. Remove from heat; set aside. 

Combine all dipping sauce ingredients in saucepan. Bring to a boil; cook 35 minutes or until half of liquid has evaporated. Reduce heat to low; keep warm.

Heat nonstick griddle to 350°F. 

Spread 1 side of each bread slice with 1/2 tablespoon butter. Layer 4 slices bread, buttered-side down, with 1 slice cheese, 1/4 onion mixture and 1 slice cheese. Top with remaining bread slices, buttered-side up. 

Place sandwiches into skillet. Cook, turning once, 15-20 minutes or until golden brown on both sides. Serve with au jus.

*Substitute 2 tablespoons apple cider vinegar