Beef & Potato Empanadas

Name: Beef & Potato Empanadas
Total time: 1 h 20 min
Yield: 13 servings
Ingredients: 1/2 cup unsalted butter frozen; 2 1/4 cups all purpose flour; 2 teaspoons salt; 1 large egg; 1/3 cup cold water; 1 1/2 tablespoons white vinegar; 1 tablespoon olive oil; 1/2 baking potato large, diced into 1/4-inch cubes; 1/2 white onion small, diced; 1/2 red pepper cored and diced; salt; pepper; 1 pound ground beef; 15 cherry tomatoes halved; 1 clove garlic diced; 1/2 bunch cilantro minced; 1 large egg; 2 tablespoons milk