Preheat oven to 425°. Line a baking sheet with foil.
In a large bowl, combine sweet potato, Cajun seasoning, pepper, salt, and cumin. Spread sweet potato mixture onto prepared pan. Bake, turning frequently, until tender, 15 to 20 minutes.
In a medium saucepan, heat 1 tablespoon oil over medium heat. Add onion; cook until tender, about 2 minutes. Add jalapeño and ginger; cook until jalapeño is tender. Remove from heat, and stir in sweet potato mixture, black beans, and cilantro. Let cool completely.
Cut Meat Pie Dough into 20 pieces. On a lightly floured surface, roll 16 pieces of dough to a 5½-inch circle, and place on a parchment-lined baking sheet. Reserve remaining dough for another use. Refrigerate for 10 minutes. Using a 5-inch round cutter, cut rounds from each piece of dough. In a small bowl, whisk together egg and 2 tablespoons water.
Place 2 tablespoons filling in center of each round. Lightly brush edges with egg wash. Fold dough over filling, and press to seal. Using a fork, crimp along edges of pie. Using a pastry wheel, cut along edges to further seal. Freeze pies before frying.
In a large Dutch oven, pour oil to a depth of 4 inches, and heat over medium heat until a deep-fry thermometer registers 370°. Line a rimmed baking sheet with paper towels, and place a wire rack on top.
Remove pies from freezer. Using a slotted spoon, gently place pies, 3 at a time, in hot oil. Fry until golden brown, about 2 minutes per side. Remove from oil, and let drain on prepared pan.
Recipe by Louisiana Cookin' at https://louisianacookin.com/a-little-meat-pie-mania/