You can use a measuring cup, but it's easier to just eyeball it. A chapatti is a thin, flat circular bread or dough. In this case, each one should be about 6 inches (15.2cm) in diameter. Use a rolling pin or press the chapattis into shape with your fingers. Use a knife to slice each one in half. Spoon 2 teaspoons of filling into the center of a piece of dough, then bring the edges together to form a cone shape. Seal the edges carefully using a little water. (You can also make paste using flour and water for easier sealing). Use your fingers to press the edges of each samosa into place. For a lovelier edge, you can use a fork to press the edges together. As you finish filling each one, set it aside on a plate or a baking sheet. Pour several inches of oil into a large dutch oven or a high-sided frying pan. Heat the oil until it reaches 350F (177C). Use a candy thermometer to test whether the oil is hot, or place a small piece of dough in the oil to see if it sizzles. Place 3 to 4 samosas in the pot to fry. Deep fry them for about 10 minutes, until both sides are golden brown. Don't try to crowd the pot with too many at once, or they may fall apart instead of cooking properly. After each batch is finished frying, use a slotted spoon to move the finished samosas to a plate lined with paper towels to drain off the extra oil. Take care not to let them fry for too long, or the dough will become tough. Hot crispy samosas are ready to eat with chutney.

Summary:
Divide the dough into eight equal portions. Roll in each round into chapattis. Cut each chapatti into two halves. Stuff and fold the samosas. Repeat with the remaining chapattis and filling. Heat the oil. Fry the samosas. Serve hot with green chutney.