In medium bowl, mash potatoes; set aside. In 6-inch skillet, heat 1 tablespoon oil and the mustard seed over medium-high heat. Once seed begins to pop, cover skillet and wait until popping stops. Add 2 tablespoons black lentils; stir-fry about 30 seconds or until golden brown; remove from heat. Stir in 1 teaspoon salt, 1/4 teaspoon turmeric, the lime juice, karhi, cilantro and 2 to 3 chiles. Add to potatoes; mix well. Shape into eighteen 1 1/2-inch balls; set aside.