Preheat oven to 400°F. Prepare a large baking sheet with parchment paper or spray a baking sheet with non-stick spray.
In a medium skillet, over medium heat, melt the unsalted butter.
Add the shallots and red pepper. Saute for about 4-5 minutes. Onions will become translucent and red pepper softens.
Add the minced garlic, stir occasionally for another minute.
Remove from heat and let cool. Set aside
In a medium bowl, mix the cooled onion/red pepper mix, crab meat, cream cheese, Old Bay Seasoning, salt, and pepper. Mix well.
Taste the mixture, if needed adjust the seasoning, to taste.
Place about a teaspoonful of the crab mixture into each mushroom cap. Place stuffed mushrooms on prepared baking sheet. Continue to stuff all mushrooms.
Combine the Panko breadcrumb and melted butter, brush butter mixture on the top of each mushrooms.
Bake stuffed mushrooms in the preheated oven for about 15 minutes. Mushrooms will be golden brown.
Be sure to check Expert Tips and FAQs above with important tips and questions that can help make a delicious recipe. Note 1: We add the Panko/butter combo - my youngest loves the crunch. If needed to limit carbs or you are keto don't add the panko mixture. Note 2: Canned crabmeat is cost-effective and works great in this recipe. If you prefer, use fresh crab.
Any nutritional data I provide is an approximation and actual dietary information can vary based on ingredients and proportion sizes.