Preheat oven to 425 degrees F (220 degrees C). Spray a baking sheet lightly with Non-Stick Baking Spray (to taste).
Remove stems from the Baby Portobello Mushroom (16 ounce). Reserve the stems. Place the mushroom caps rounded side down onto the baking sheet.
Lightly brush each mushroom cap with Butter (1 teaspoon). Set aside.
Finely chop the mushroom stems.
Place chopped mushroom stems in a skillet with the Pecans (1/3 cup) and heat over medium. Stir and cook until the mushrooms cook down and excess moisture is gone. Stir frequently to prevent burning.
In a large bowl combine the mushroom and pecan mixture with the Cream Cheese (4 ounce), Sharp Cheddar Cheese (1/2 cup), Scallion (1/4 cup), Cooked Bacon (2 slice), Panko Breadcrumbs (1/4 cup), Garlic (1/2 teaspoon), and Ground Black Pepper (1/2 teaspoon). Combine well.
Stuff each mushroom cap with the stuffing mixture. Top each stuffed mushroom with the remaining Sharp Cheddar Cheese (1/4 cup)
Bake for 10 to 15 minutes. Serve hot and enjoy!