In a bowl, mix the flour and salt.
Cut in the cold butter until the mixture resembles coarse crumbs.
Gradually add cold water, mixing until the dough forms.
Wrap the dough in plastic wrap and refrigerate for 30 minutes.
In a skillet, sauté onions and bell peppers until soft.
Add shredded chicken, cumin, and paprika; mix well and cook for 5 minutes.
Preheat the oven to 375°F (190°C).
Roll out the dough on a floured surface to about 1/8 inch thick.
Cut out circles using a large cookie cutter.
Place a spoonful of filling in the center of each circle, fold, and crimp the edges.
Brush the tops with the beaten egg.
Bake for 20-25 minutes until golden brown.