Make the Pie Dough:
Whisk flour and salt in a bowl. Rub in butter until the mix looks like coarse crumbs.
Mix egg, vinegar, and ¼ cup water, then add to flour mixture. Gradually add more water until a pliable dough forms.
Knead gently, fold into thirds twice, shape into a disc, wrap in plastic, and chill for at least 1 hour.

Prepare the Filling:
In a skillet over medium-high heat, cook onions in a little oil until softened.
Add garlic, ground chorizo, pork, paprika, cayenne, and salt. Cook for 15–20 minutes, breaking up the meat until fully cooked. Drain excess fat and chill the filling.

Roll and Cut the Dough:
Preheat oven to 375°F and line a baking sheet with parchment.
Roll out dough to about 3mm thick. Use a 4-inch pumpkin-shaped cookie cutter to cut 30 pieces.
On 15 pieces, use a knife or mini cutters to make jack-o’-lantern faces.

Assemble the Pies:
On each plain pumpkin, add cheese and a spoonful of chilled filling.
Moisten edges with water and top with a face cutout. Seal edges and crimp with a fork.

Bake:
Arrange pies on baking sheet. Brush tops with egg wash.
Bake for 20–30 minutes or until golden brown. Let cool slightly and serve warm!