In a large bowl, whisk together flour, salt, and baking powder. Cut butter into flour using your hands or a pastry cutter until pea-sized. Add water and egg and mix until a dough forms. Turn dough out on
a lightly floured surface and knead until smooth, about 5 minutes.
Wrap in plastic wrap and refrigerate for at least 1 hour.
FOR AIR FRYER
In a large skillet over medium heat, heat oil. Add onion and cook until soft, about 5 minutes, then add garlic and cook until fragrant, 1
minute more. Add ground beef and cook, breaking meat up with a wooden spoon, until no longer pink, 5 minutes. Drain fat.
Return pan to medium heat, and stir tomato paste into beef. Add
oregano, cumin, and paprika, and season with salt and pepper. Add
tomatoes and jalapeños and cook until warmed through, about 3 minutes. Remove from heat and let cool slightly.
Place dough on a lightly floured surface and divide in half. Roll one
half out to ¼” thick. Using a 4.5” round cookie cutter, cut out rounds.
Repeat with remaining dough.Reroll scraps once to cut out more
Lightly moisten outer edge of a dough round with water and place
about 2 tablespoons filling in center and top with cheddar and Monterey. Fold dough in half over filling. Use a fork to crimp edges together, then brush with egg wash. Repeat with remaining filling and dough.
Place empanadas in a parchment-lined Air Fryer basket, making
sure they don't touch, and cook in batches at 400°F for 10 minutes.
Garnish with cilantro and serve with sour cream.