01 -
Preheat the oven to 375°F (190°C).
02 -
Lightly grease an 8x13 inch baking pan.
03 -
In a large bowl, combine the crabmeat with the lemon juice, panko bread crumbs, melted butter, ⅕ cup grated Parmesan cheese, Dijon mustard, horseradish, garlic powder, and onion powder. Mix thoroughly.
04 -
Scoop the crab mixture using a cookie scoop and fill the mushroom caps with the mixture.
05 -
Sprinkle the remaining grated Parmesan cheese on top of the stuffed mushrooms.
06 -
Bake in the preheated oven until the mushrooms are tender, about 15-20 minutes.
07 -
Remove the mushrooms from the oven and serve immediately.