Ingredients
2 tbsp. butter
1 large onion, thinly sliced
kosher salt
Freshly ground black pepper
1 tbsp. fresh thyme leaves
2 tbsp. dry white wine
1 lb. ground beef
1 packet French onion soup mix (such as Lipton’s)
1 tbsp. Worcestershire sauce
2 cloves garlic, minced
1 large egg
2 c. shredded Gruyère
1 tbsp. extra-virgin olive oil
4 Hamburger buns
4 pieces lettuce
4 slices tomato
Preparation
Step 1In a large skillet over medium-low heat, melt butter. Add onions and season with salt and pepper. Stir in thyme and caramelize until golden, 15 minutes. Stir in white wine and continue to cook until absorbed.Step 2Make patty mixture: In a large bowl, combine ground beef, French onion soup mix, Worcestershire, garlic and egg and season with salt and pepper. Mix until fully combined.Step 3Form 8 thin patties. Top 4 patties with 1 tablespoon each gruyère and caramelized onions. Top each with remaining patty and seal sides.Step 4In a skillet over medium-high heat, heat oil. Cook until medium, 5 minutes per side. Top with remaining gruyère and cover with lid to melt, 1 minute.Step 5Serve burgers on buns with lettuce and tomato.
