Loaded Burger with Panko-Breaded Portabella Mushroom Bun

This low-carb burger is topped with all the best ingredients, and the portabella mushroom takes the place of a traditional bun for a satisfying, savory bite.

Ingredients for the Burger:

• 4 large portabella mushroom caps (about 4-6 inches in diameter), stems removed
  

• 4 beef patties (about 4-6 oz each)
  

• 1 avocado, sliced
  

• 1 medium tomato, sliced into 4 rings
  

• 1 small onion, sliced into rings
  

• 4 large eggs (for frying)
  

• 1 cup panko breadcrumbs (low-carb version or homemade)
  

• 2 tbsp olive oil
  

• Salt and pepper to taste
  

• Lettuce leaves (optional, for extra crunch)
  

Instructions for the Burger:

1. Preheat your grill or Blackstone to medium-high heat (about 375°F).
   

2. Brush the portabella mushrooms with 2 tbsp olive oil and season with salt and pepper. Grill the mushroom caps gill side up for 3-4 minutes per side until tender.
   

3. Meanwhile, season the beef patties with salt and pepper, and grill them for 3-5 minutes per side, or until your preferred level of doneness is reached (internal temperature of 160°F for medium).
   

4. To prepare the panko-breaded mushrooms, dip the mushroom caps in 1 beaten egg, then coat them in 1 cup panko breadcrumbs. Lightly fry them in a skillet with 2 tbsp olive oil over medium heat for 2-3 minutes per side, until golden and crispy.
   

5. While the mushrooms are frying, fry 4 eggs sunny-side up in a separate skillet over medium heat (about 3-4 minutes per egg).
   

6. Once everything is cooked, assemble the burger: place a grilled portabella mushroom on the bottom, top with a beef patty, a fried egg, slices of avocado, tomato, and onion rings.
   

Top with the second grilled portabella mushroom to complete the "bun" and serve with a side of lettuce if desired.