In a medium saucepan, combine split peas and water. Bring them to a boil, reduce heat, cover, and simmer until peas are tender, about 35 to 45 minutes. Drain peas, and set aside.
Boil potatoes with 1 teaspoon salt until they are tender. Drain and set aside.
Meanwhile, prepare the dough. Combine flour and salt in a medium-sized bowl. Make a well in the center and add yogurt and oil. Mix ingredients until they form a ball. Add water ½ tablespoon water if needed to bring the dough together.
Turn the dough onto a lightly floured surface and knead it until it is smooth, about 2 to 3 minutes. Cover dough, and set it aside for 30 minutes while preparing the filling.
Prepare the filling by heating 1 tablespoon of extra virgin olive oil in a heavy skillet.
Add onions and cook, stirring frequently, until translucent. Add the ginger and chili, continue stirring for another minute.
Next, add coriander, garam masala, and salt, and cook, stirring, for about a half minute more.
Transfer the cooled potatoes to a mixing bowl and mash with a potato masher. Add the cooked peas, cooked onion mixture and chopped cilantro, mix well and adjust seasoning to taste. Set filling aside.
If baking the samosa preheat the oven to 350 F / 180 C. Line a baking tray with baking paper.
On lightly floured surface, roll out the dough into a rectangle measuring about 12 x 18 inches. Cut dough into 3-inch squares.
Place 1 tablespoon of filling on each square. Use your fingers to moisten edges of dough with water, and fold dough diagonally in half to make a triangle. Press edges firmly together to seal in the filling.