Ingredients
4 (4") portobello mushrooms, stems and gills removed
1/2 c. all-purpose flour
1 c. shredded Muenster
1 c. shredded cheddar
1/4 tsp. garlic powder
1/2 tsp. kosher salt, divided
1/2 tsp. freshly ground black pepper
3 large eggs, divided
2 c. panko bread crumbs
Vegetable oil, for frying
4 potato buns, toasted
2 plum tomatoes, sliced
4 leaves green leaf lettuce
2 tbsp. mayonnaise
1 tsp. Dijon mustard
1 tsp. ketchup
1 tsp. hot sauce
Preparation
Step 1Make burgers: In a wide bowl, dredge bottom side of mushroom caps in flour.Step 2In a medium bowl, combine cheeses, garlic powder, 1/4 teaspoon salt, pepper, and 1 lightly beaten egg. Divide among caps, gently pressing to flatten stuffing.Step 3In another wide bowl, beat remaining 2 eggs and 1/4 teaspoon salt. Dredge stuffed caps in flour, gently patting any excess, then coat in egg mixture. Finally, in a third wide bowl, dredge in panko, gently pressing to help it stick. Refrigerate until firm, at least 15 minutes.Step 4Make sauce: In a small bowl, combine mayo, mustard, ketchup, and hot sauce.Step 5In a large pot over medium-high heat, heat 3" oil to 350º. Fry mushrooms, two at a time, until golden on both sides, 4 minutes total. Transfer to a paper towel-lined plate.Step 6Spread sauce on burger buns and top with tomatoes, lettuce, and fried mushrooms.
