Ingredients

• Peanut oil, for frying, enough to fill your skillet 1 to 11/2 inches deep
• 4 round pineapple slices (either fresh or canned), each justover a 1/4-inch thick
• Butter, for grilling
• 4 onion rolls, split, buttered and griddled
• 1 cup all-purpose flour
• 3 large eggs, beaten
• 2 cups panko breadcrumbs
• Kosher salt and freshly ground black pepper
• 4 portobello mushroom caps (about 1 pound), gentlycleaned and gills removed
• 1/2 cup Japanese mayonnaise (or regular if you can't findit)
• 4 teaspoons teriyaki sauce
• 1/2 small red onion, thinly sliced
• 4 to 8 leaves red leaf lettuce

Instructions

1. Heat the peanut oil to 350 degrees F in a large cast-iron skillet.
2. Heat a grill pan over medium-high heat. Grill the pineapple slices to get nice grill marks, about 2 minutes per side. Butter and grill the buns as well.
3. Set up a breading station of flour, eggs and panko seasoned with salt and pepper, in 3 separate shallow dishes. Dredge each mushroom cap in the flour first, then the egg and finally the panko. Fry the breaded mushrooms until golden brown and cooked through, 4 to 5 minutes. Drain on a baking sheet lined with a cooling rack or paper towels.
4. Whisk together the mayonnaise and teriyaki sauce in a small bowl.
5. For the sandwich build: Spread some teriyaki mayo on the bottom and top halves of the buns. Top the bottom bun with a pineapple slice, a fried portobello mushroom cap, some onion slices and red lettuce leaf. Oh man!