In a large saucepan, heat 2 tablespoons of the oil until shimmering. Add the onions and cook over moderate heat until softened, about 8 minutes. Add the ginger paste and cook until it begins to brown, about 3 minutes. Add half of the tomatoes along with the coconut milk, peanuts, 1/4 cup of the shredded coconut and 2 tablespoons of the cilantro and cook until slightly thickened, about 5 minutes.