1. Prepare the Dough:

• In a large mixing bowl, combine the masa harina, sugar, baking powder, and salt.
• Add the melted butter and mix it in well until the dough has a crumbly texture.
• Gradually add the warm water, a little at a time, and mix until the dough comes together. The dough should be smooth, slightly moist, and pliable but not sticky. You may need to adjust the water to get the right consistency.
• Cover the dough with a clean cloth and let it rest for about 10 minutes to allow the masa to hydrate properly.

2. Make the Bean Filling:

• If using cooked black beans, mash them in a bowl using a fork or potato masher until smooth (you can leave a few chunks for texture if desired). If you’re using canned refried black beans, just heat them slightly in a small pan and mix in the sugar, cinnamon, and vanilla extract until well combined.
• Taste the mixture and adjust the sweetness by adding more sugar if necessary. If you prefer a smoother texture, you can blend the bean mixture in a food processor until creamy.
• Set the bean filling aside to cool slightly.

3. Shape the Empanadas:

• Take small portions of dough (about 2-3 tablespoons each) and roll them into smooth balls.
• Place each ball between two pieces of wax paper or plastic wrap. Use a rolling pin to gently flatten the dough into a round disk (about 4-5 inches in diameter).
• Spoon a small amount of the sweetened bean filling (about 1 tablespoon) into the center of each dough disk.
• Carefully fold the dough over the filling to form a half-moon shape. Press the edges together firmly to seal the empanada, ensuring the filling stays inside. You can use a fork to crimp the edges if you prefer.

4. Fry the Empanadas:

• Heat vegetable oil in a large frying pan over medium heat. You’ll need enough oil to submerge at least half of each empanada.
• Once the oil is hot (test by dropping a small piece of dough in the oil — if it sizzles immediately, the oil is ready), gently place the empanadas in the pan, being careful not to overcrowd the pan.
• Fry the empanadas for about 2-3 minutes on each side, or until golden and crispy. Use tongs to flip them carefully to ensure even cooking.
• Remove the empanadas from the oil and place them on a paper towel-lined plate to drain excess oil.

5. Serve:

• Once the empanadas have cooled slightly and the filling is no longer too hot to touch, they are ready to serve. You can sprinkle them with a little powdered sugar for extra sweetness if desired.
• Serve the empanadas de frijoles warm with a side of coffee or a cold beverage of your choice.