Beef Empanadas

In a large bowl, whisk flour, baking powder, and salt. Cut butter into dry ingredients with your hands or a pastry cutter until pea-sized pieces form. Add egg and 3/4 cup water and mix with a wooden spoon until a dough forms.

Turn out dough onto a lightly floured surface. Knead until smooth, about 5 minutes.

Wrap in plastic wrap and refrigerate for at least 1 hour and up to overnight.

Preheat oven to 400°. Line 2 large baking sheets with parchment. In a large skillet over medium heat, heat oil. Add onion and cook, stirring, until softened, about 7 minutes. Add garlic and cook, stirring, until fragrant, about 1 minute more. Add beef and cook, breaking meat up with a wooden spoon, until no longer pink, about 5 minutes. Drain fat.

Return pan to medium heat and stir tomato paste into beef. Add oregano, cumin, and paprika; season with salt and pepper. Add jalapeños and tomatoes and cook, stirring occasionally, until warmed through, about 3 minutes. Let cool slightly.

Turn out dough onto a lightly floured surface and divide in half. Roll one half to 1/4" thick. Using a 4.5" round cookie cutter, cut out rounds. Repeat with remaining dough. Reroll scraps once to cut out more rounds.

Lightly moisten outer edge of a dough round with water. Place about 2 tablespoons filling in the center. Top with cheddar and Monterey Jack. Fold dough in half over filling. Using a fork, crimp edges together. Repeat with remaining filling and dough.

In a small bowl, beat egg with a splash of water. Place empanadas on prepared baking sheets and brush with egg wash.

Bake empanadas until golden brown and filling is warmed through, about 25 minutes.

Top with cilantro and serve with sour cream alongside.