Make the Dough:

In a large mixing bowl, mix flour and salt.
Add the oil and then start mixing with your fingers, rub the flour with the oil until the oil is well incorporated.
Once incorporated, the mixture resembles crumbs.
Start adding water, little by little and mix to form a stiff dough (the dough shouldn’t be soft).
Cover the dough and let it rest for 30 minutes.
Prepare the Filling:

Roughly chop/mash boiled potatoes and set aside.
Heat oil in a large pan, add cumin seeds, coriander seeds, chili powder, turmeric, and garam masala, cook for 30-60 seconds to release the flavors.
Add crushed garlic, ginger paste, chopped green chili and cook for 1 minute.
Add chopped onion and sauté for 3-4 minutes.
Add chopped potatoes, green peas, lemon juice, water, and salt, cook for 4-5 minutes, stirring frequently.
Add crushed cashew and cook for 1 minute more.
Turn off the heat, add chopped coriander leaves, stir well, and set aside to cool.
Shape the Samosas:

Once the dough has rested, give it a quick knead.
Divide the dough into 6-7 equal parts and shape into balls.
Roll out each ball into an oval, about 6-inches long and 4 inches wide.
Cut it into two parts.
Coat the edges of each semicircle with water.
Pick the two corners of the semicircle and bring them together, edges overlapping slightly, to form a cone.
Press down on the seam to stick it.
Fill the samosa with the potato filling, around 1-2 tablespoons. Don’t overfill.
Brush the edges again with water, then pinch the edges and seal the samosa.
Repeat the same process with the remaining dough and filling, keep filled samosas covered with a moist kitchen towel while working.
Fry the Samosas:

Heat oil to 350F (175C).
Drop the samosas into hot oil, 4-5 pieces at a time.
Reduce the heat to medium.
Fry for 4-5 minutes, until golden and crisp.
Serve:

Drain on paper towels before serving.
Serve with your favorite sauce.
Enjoy your delicious homemade samosas!