The Egg-Topped Burger

Ingredients 

For the sauce:
1/4 cup dijon mustard 
1/4 cup mayonnaise 
2 tablespoons freshly chopped rosemary 
2 teaspoons freshly squeezed lemon juice 
Kosher salt and black pepper 

For the burger:
1 pound ground chuck beef, (80 percent lean)
Kosher salt and black pepper
4 tablespoons canola oil, divided
4 ounces grated sharp cheddar cheese 
4 large whole eggs, fried sunny-side up
4 seeded hamburger buns, split in half and toasted

Toppings: 
1 tomato on the vine, cut into 5 rounds (1/8-inch thick)
1 cup baby portobella mushrooms, cut into (1-4-inch pieces), sautéed 1 whole onion, cut into rings and sautéed 
Arugula (for topping) 
Ketchup. 

Directions

In a bowl, combine the mustard, mayonnaise, rosemary, and lemon juice. Mix until well incorporated and smooth.  Season with salt and pepper to taste. Set aside. 

Divide the beef into 4 equal parts then form meat into patties. Season each patty with salt and pepper. Heat the 2 tablespoons oil in a medium skillet and cook patties over medium-high heat for 5 to 6 minutes on each side. Sprinkle cheese over the patties in the last 2 minutes of cooking, use as much as you like for each patty. 

In a separate large skillet heat 2 tablespoons oil over medium-high heat and fry the eggs. For a runny-yolk, tilt the skillet towards you and using a spoon drizzle the hot oil over the egg whites, about two minutes. Set aside. 
 
Prepare your burger bun and begin to assemble: bun, mayonnaise sauce, burger with cheese, tomato, mushroom, pinion, arugula, ketchup, bun. Enjoy! 

---