Clean mushrooms with a damp paper towel. Set aside.

Pour 2 to 3 inches of oil in a heavy saucepan. Place over medium high heat.

Place flour, salt, mustard, paprika and pepper in paper or plastic bag. Shake well to mix completely. Set aside.

Place buttermilk in small bowl.

Throw 3 or 4 mushrooms in buttermilk. Turn to coat fully.

Place wet mushrooms in the bag with flour mixture. Shake to coat fully.

Remove breaded mushrooms to a plate and continue until all mushrooms are breaded.

When oil is hot and shimmering, carefully place a few mushrooms at a time into the saucepan. Fry for 2 to 3 minutes until golden brown, turning occasionally.

Remove to a paper towel-covered plate to drain.

Continue with remaining breaded mushrooms until all are fried.