Lotus Seed Paste

1.Rinse lotus seeds and soak in a large bowl of water until softened, at least 4 hours or overnight.
2.Tear each seed in half and remove the small bitter sprout (technically the cotyledon) in the center.
3.Place lotus seeds in a large pot and add enough water to completely cover. Bring to a boil over high heat, then lower heat and simmer, adding more water if necessary to keep seeds covered, until tender, about 1 hour.
4.Reserve 1 cup of cooking water, then drain seeds and transfer to a food processor or blender, add a splash of reserved water, and process to a smooth paste, adding more if necessary. For a smoother texture, press paste through a fine sieve.
5.Add paste and oil to a nonstick skillet and heat over medium heat, stirring with until oil is incorporated. Add 1/2 cup sugar and stir until incorporated. Taste, and if you want the paste more sweet, add more sugar 1 tablespoon at a time, until desired sweetness.
6.Remove from heat and set aside. The lotus-seed paste can be made in advance and refrigerated for up to 3 days, or frozen for up to 6 months.