Slice the stems of the mushrooms into thick slices. Using a small ring, cut out circles from the center of each mushroom slice.
In a bowl, prepare the batter by combining the flour, water, coarse salt, black pepper, garlic powder, and sweet paprika. Mix well.
Dip each mushroom slice into the batter, ensuring it is coated evenly. Then transfer the coated mushrooms to a separate bowl with the bread crumbs, and coat them thoroughly.
Heat oil in a frying pan. Fry the coated mushrooms until they turn a golden brown color. Alternatively, you can bake them in a preheated oven at 355 ℉ (180 ℃) for 20 minutes.
Serve the crispy mushrooms on the side with your preferred sauce. We recommend a delightful aioli dip made with mustard and garnished with scallions.