The secret to making the mushrooms that top this Miesfeld’s burger so succulent is bacon fat. Yes, we shamelessly baste them with it, along with a little olive oil to keep them moist. 

4 slices thick-cut bacon
¼ cup extra-virgin olive oil,
4 medium portobello mushrooms, about 4 inches in diameter each
freshly ground black pepper
1 ½ pounds Miesfeld’s Ground Chuck (80% lean)
Kosher Salt
4 thin slices Havarti cheese
4 hamburger buns
4 tablespoons dijon mustard
4 crisp lettuce leaves

In a large saute pan over medium heat, cook the bacon until crisp, 10 to 12 minutes, turning occasionally. Remove the bacon and set aside on paper towels to drain. Reserve the bacon fat in the pan and add the olive oil.

Remove and discard the mushroom stems. Clean the caps with a moist paper towel and, using a small spoon, scrape out the black gills from inside the caps. Generously brush both sides of the mushrooms with the bacon fat and oil moisture. Season with pepper.

Gently shape the ground chuck into four burgers of equal size and thickness (about ¾ inch thick), and season both sides with salt and pepper.

Grill the mushrooms and burgers over direct medium heat until the mushrooms are tender and juicy and the burgers reach an internal temperature of 160 degrees Fahrenheit for medium. 8 to 10 minutes, turning once halfway through grilling time. Top each burger with a slice of the cheese during the last minute or two of grilling time and allow the cheese to melt. During the last 30 seconds, grill the buns over direct medium heat until lightly toasted. Spread the mustard on the toasted buns. Serve the cheeseburgers hot on the buns, topped with a slice of bacon, a mushroom cap, and a lettuce leaf.