01 - Pat mushrooms completely dry with paper towels. If mushrooms are large, halve or quarter them to create bite-size pieces for even cooking.
02 - Arrange three shallow bowls: combine flour with garlic powder, smoked paprika, salt, and black pepper in the first; whisk eggs with milk in the second; place breadcrumbs in the third.
03 - Dredge each mushroom piece in seasoned flour, shaking off excess. Dip into egg mixture, allowing excess to drip off, then press firmly into breadcrumbs to coat completely. Transfer to a baking sheet.
04 - Pour vegetable oil to a depth of 1 inch in a deep skillet. Heat to 350°F over medium-high heat.
05 - Fry mushrooms in small batches for 3 to 5 minutes, turning occasionally, until golden brown and crispy. Remove with slotted spoon and drain on paper towels.
06 - Melt butter in a saucepan over medium heat. Whisk in flour and cook for 1 to 2 minutes, stirring constantly to create a roux.
07 - Slowly whisk in milk until smooth. Add salt, pepper, garlic powder, and cayenne. Simmer for 3 to 5 minutes, whisking constantly, until thickened. Adjust seasoning as needed.
08 - Transfer fried mushrooms to serving plates and spoon warm gravy generously over the top. Serve while hot and crispy.