In a large mixing bowl, combine all-purpose flour, salt, and baking powder. Slowly add vegetable oil, followed by warm water, mixing until a cohesive dough forms. Knead the dough on a floured surface for about 5 minutes until smooth. Let the dough rest covered for 30 minutes.

Heat a skillet over medium heat and add the ground beef or turkey. Cook until browned, about 6-8 minutes. Drain any excess fat, then add taco seasoning and a splash of water, stirring to combine. Cook until thick and fragrant, around 4-5 minutes, then remove from heat.

Divide the rested dough into 8 equal portions. Roll each piece into a 6-inch circle on a floured surface, keeping rolled circles covered to prevent drying out.

Place a spoonful of the cooled filling on one half of a dough circle. Sprinkle cheese, diced tomatoes, chopped onions, and cilantro on top. Fold the other half over and seal the edges firmly.

Heat vegetable oil to 350°F (175°C) in a deep pan. Fry taco pockets in batches for 3-4 minutes per side until golden brown and crispy. Use a slotted spoon to transfer cooked pockets to a plate lined with paper towels.

Serve hot, garnished with fresh cilantro if desired, and paired with sour cream and various salsas for dipping.