Step 1: Prepare the Dough

1. In a large bowl, mix the sourdough discard, whole wheat flour, salt, and baking powder.
2. Add the olive oil or melted butter and mix until the mixture resembles coarse crumbs.
3. Gradually add cold water, kneading gently until a smooth dough forms. Adjust consistency with flour or water as needed.
4. Cover and let rest for 30 minutes to relax the gluten and improve texture.

Step 2: Make the Filling

1. In a skillet, heat a small amount of oil over medium heat.
2. Add onions and bell peppers, cooking until soft.
3. Stir in the shredded chicken or lentils, along with cumin, smoked paprika, salt, and pepper.
4. Cook for a few minutes, then remove from heat and allow to cool.
5. Mix in shredded cheese and chopped boiled egg if using.

Step 3: Assemble the Empanadas

1. Preheat oven to 375°F (190°C). Line a baking sheet with parchment paper.
2. Roll out the dough on a lightly floured surface to about ⅛-inch thickness.
3. Cut circles using a 4- to 5-inch round cutter.
4. Place a spoonful of filling in the center of each circle.
5. Fold the dough over the filling to form a half-moon shape and press the edges together. Use a fork to crimp and seal the edges.
6. Brush the tops with the beaten egg and sprinkle with sesame seeds if desired.

Step 4: Bake the Empanadas

1. Arrange the empanadas on the prepared baking sheet, leaving some space between them.
2. Bake for 20–25 minutes, or until golden brown.
3. Let cool slightly before serving.