Preheat oven to 375-degrees and line large baking sheet with parchment paper.
Combine filing ingredients in a medium-sized mixing bowl and set aside.
Next, make the dough by combining flour, baking powder and salt in a mixing bowl. Using a fork (or your hands), mix in Greek yogurt until crumbly. From here, use your hands to knead the dough into a ball. You want the dough to still have moisture, but not stick to your hands.
Sprinkle extra flour on a clean surface and roll out dough until it’s very thin (as if you were making a thin-crust pizza). Using a glass, small bowl, or cookie cutter, cut out as many rounds as you can. Roll remaining dough back out and form into more rounds (like you would when making Christmas cookies). I got 14 rounds using a tall pint glass.
Fill each circle with ~2-3 tablespoons of sweet potato mixture, then brush edges of dough with the egg wash. Fold one edge over to the other and crimp with a fork to seal.
Place assembled empanadas on a parchment-lined baking sheet. Brush tops of empanadas with remaining egg wash, then bake for 22-25 minutes, or until golden brown on top. Serve with salsa or other dipping sauce of choice. Enjoy!