In a medium bowl, combine the flour, garlic powder, onion powder, paprika, salt, and black pepper. Mix well and set aside.

In another bowl, whisk together the egg and buttermilk until fully combined.

Dip each mushroom into the buttermilk mixture, allowing any excess to drip off, then coat it in the seasoned flour mixture. Shake off any excess flour.

Return the floured mushroom to the buttermilk mixture, then roll it in the breadcrumbs until fully coated. Place the breaded mushrooms on a plate.

In a large skillet, heat about 1 inch of vegetable oil over medium heat until it reaches 350°F.

Carefully add the breaded mushrooms to the hot oil in batches, frying for about 3-4 minutes or until golden brown and crispy.

Use a slotted spoon to remove the mushrooms from the oil and transfer them to a paper towel-lined plate to drain excess oil.

Serve hot with your favorite dipping sauce, such as ranch or marinara.