Combine the feta cheese, hot sauce, and one egg in a medium-sized bowl and whisk until thoroughly combined; set aside.

In your mixer’s bowl, combine flour and sour cream; mix with the dough hook until a soft ball forms. Adjust with more flour or sour cream as needed.

Lightly flour your working surface and turn out the dough.

Roll out the dough to a 1/4-inch thickness, using multiple passes for even thickness.

Cut out 3-inch rounds using a cookie cutter; reroll scraps as needed.

Place a spoonful of filling into the center of each round and fold in half, sealing edges with a fork.

Heat oil in a skillet to 350°F.

Fry pierogies in hot oil for 2 minutes, flip, then cook until browned.

Remove and drain on paper towels.

Serve hot with sour cream, caramelized onions, or salsa.