Don’t have a candy thermometer to test the oil’s temperature when frying these fritters? See if it’s ready by dipping in a wooden spoon handle or a wooden chopstick; if the oil surrounding it produces a steady, but not vigorous, stream of bubbles, it’s hot enough.
Put the potato in a small saucepan. Fill the pan with water to cover, bring to a boil over high heat, then reduce to a simmer and cook for 20 minutes or until fork tender. Remove and let cool enough to handle. Peel and cut unto 1/4-inch dice.
In a food processor, process the lentils, ginger, and chiles to a fine paste. Transfer one-third of the mixture to a blender and blend, adding a little water, a tablespoonful at a time, to make a very smooth paste. In a bowl, mix both lentil pastes with the potato, peas, garam masala, cayenne, cilantro, and 3/4 teaspoon salt. Beat with a spoon until light and fluffy.