Sweet Potato and Pea Samosas

Name: Sweet Potato and Pea Samosas
Ingredients: 3 medium to large sweet potatoes peeled and chopped into cubes; 1 cup peas I used frozen peas; 1 teaspoon vegetable oil; 1/2 teaspoon turmeric powder; 1/2 teaspoon chaat masala found in Indian stores; 1/2 teaspoon garlic powder; 1 teaspoon red chili flakes; 1/2 teaspoon cumin powder; 1 inch piece of ginger grated; Salt to season; 1 puff pastry sheet I used 1 sheet of Blätterteig, available in Swiss supermarkets; 1 egg beaten, for the egg wash