In a large bowl, combine flour, salt, and baking powder. Gradually add oil and warm water. Stir until a soft dough forms, then knead for about 5 minutes until smooth. Cover and let rest for 30 minutes.

Heat a skillet over medium heat. Add ground meat and cook until browned. Drain excess fat, then add taco seasoning and water; cook until thickened. Remove from heat and let cool.

In a deep pan, heat oil to 350°F (175°C). Test by dropping a piece of dough in; if it sizzles, the oil is ready.

Divide dough into 8 portions and roll each into a circle about 6 inches in diameter. Cover with a towel to prevent drying out.

On one half of each circle, place beef mixture, cheese, onion, tomatoes, cilantro, and jalapeños. Be careful not to overfill.

Fold the dough over the filling, pressing edges together. Crimp with a fork to seal securely.

Fry sealed pockets in hot oil for about 3–4 minutes on each side until golden brown. Use a slotted spoon to flip gently.

Remove from oil and drain on paper towels. Serve warm with sour cream and salsa.