Preheat oven to 350 degrees. Place a cast iron skillet into the oven in the last 5 minutes of preheating to preheat the skillet.

In a medium-sized bowl, mix together the eggs, feta cheese, and baking power until well combined.

Lay out one sheet of phyllo dough and lightly brush with butter. Scoop a few small spoonfuls of filling randomly across the phyllo sheet and roll up the phyllo into a log.

Pull the cast iron out of the oven and wind up the phyllo log, placing it in the center of the skillet. Repeat this process, placing phyllo logs with filling concentrically until you have either used up all the filling or filled up the skillet.

Lightly brush the top of the phyllo logs with some butter and place in oven, baking for 25 minutes. Let it cool off slightly before serving although it can be eaten either warm or cold.