In a large bowl, combine the flour and 1/4 teaspoon of the salt and then rubbing 1/4 cup of the ghee into the flour until well combined and mixture resembles coarse crumbs. Add the water, a tablespoon at a time, until the pastry comes together to form a ball, about 10 tablespoons. Knead the dough lightly and then form into a disk, wrap in plastic wrap and transfer to the refrigerator to rest for at least 1 hour.

While the dough is resting, make the filling. Peel the potatoes and cut into small dice and place in a bowl. Heat the remaining 1/4 cup of ghee in a medium skillet and add the onion. Cook until the onion is lightly caramelized, about 6 minutes. Add the ginger, chile, coriander, garam masala, and cumin seeds and cook until the spices are fragrant, about 2 minutes. Add the potatoes, 1 teaspoon of the remaining salt, and 1/8 teaspoon of the pepper and cook, stirring, until well combined, about 6 minutes. Add the peas and 3 tablespoons of the cilantro and set aside to cool completely.

While the filling is cooling, make the yogurt dipping sauce. In a small serving bowl, combine the yogurt, remaining tablespoon of cilantro, mint, green onion, lemon juice, remaining 1/4 teaspoon of salt and remaining 1/8 teaspoon of pepper. Set aside, refrigerated, until ready to serve the samosas.

Divide the samosa dough into 10 portions and roll each piece of dough into a circle about 5 inches in diameter. Cut each circle in half. Lightly moisten the straight edge of each half circle with water, and press together to seal; you should now have a cone-shaped portion of dough. Carefully spoon about 2 heaping tablespoons of the filling into the dough cone, then moisten the remaining edges with a bit of water and press together to seal. Repeat with the remaining portions of dough and filling.

When you are ready to fry the samosas, heat a large saucepan filled with at least 2 inches of oil to about 340 degrees F. Fry the samosas, a few at a time, and stirring to promote even cooking, until golden brown, about 4 minutes. (Note: these will float to the surface of the oil long before they are ready to be removed; make certain to cook them until the pastry is crispy and golden brown.) Remove using a slotted spoon and transfer to a paper-lined plate to drain. Repeat until all samosas have been fried. Serve with chutney, if desired.