In a large straight sided skillet heat oil on medium-high. Add onion, cook stirring, until translucent, 3 minutes. Stir in curry paste, chickpeas, potatoes, coconut milk, and 1/3 cup water. Bring to a boil. Reduce heat and simmer, covered, stirring occasionally, until potatoes are almost tender, about 8 minutes. Add spinach, stir until wilted. Season with salt and pepper. Cool completely.

On a lightly floured surface, roll 1 piece of dough into an 18-inch square (about 1/8-inch thick). Cut out six 6-inch squares. Brush edges with egg. Place 1/3 cup filling on one side of a square. Fold dough over to enclose filling creating a triangle. Press edges to seal. Cut 3 small vents in top. Place on parchment-lined baking sheet. Repeat with remaining dough and filling.

To Freeze and Bake Later: Freeze in single layer on baking sheet, 2 hours. Transfer to freezer bags. Will keep, frozen, for up to 1 month. To serve, heat oven to 375 degrees. Brush hand-pies with egg. Place on a baking sheet and bake until golden brown and bubbling, 45 minutes.

To Bake and Serve: Preheat oven to 375 degrees. Refrigerate pies on baking sheet for 30 minutes. Brush with egg then bake until golden brown and bubbling, about 30 minutes.