Yin-Yang Tang Yuan (Sweet Sticky Rice Balls in Soup)

1. Using a mortar and pestle, grind sesame seeds. Add 3 tablespoons melted coconut oil, and mash until a slightly coarse paste forms, 5 to 7 minutes. Transfer mixture to a small bowl; stir in granulated sugar and remaining 2 tablespoons melted coconut oil. Chill, uncovered, just until sesame mixture holds it shape when rolled, about 7 minutes. Roll sesame mixture into 32 balls (1 level teaspoon each); arrange on a baking sheet. Chill at least 10 minutes or until ready to use.

2. While sesame balls chill, lightly dust a baking sheet with white rice flour; set aside. Bring a large pot of water to a boil over high. While water comes to a boil, stir together glutinous rice flour and white rice flour in a large heatproof bowl. Stir in 1 cup water until flour mixture absorbs all water. Knead until a smooth ball forms, about 3 minutes. Divide dough in half.

3. Place 1 dough portion on a work surface very lightly dusted with white rice flour; cover remaining dough portion with a very damp paper towel. Gently roll dough portion on work surface into a 16-inch-long rope (about 1 inch thick). Dust knife blade with white rice flour, and slice rope crosswise into 16 (1-inch-long) pieces (1/2 ounce each). Cover dough pieces with a very damp paper towel. Transfer 16 chilled sesame balls to a plate. Working with 1 dough piece at a time, roll dough piece into a ball using your hands. Using your thumb, make a deep indentation in ball. Place 1 sesame ball in indentation; spread dough evenly around sesame ball to enclose. Using your hands, gently roll into a smooth ball without any seams or cracks. Place rice ball on reserved floured baking sheet. Repeat process with remaining 15 dough pieces and remaining 15 sesame balls. If dough begins to crack when assembling, wet hands with water, shake off excess, and gently knead dough piece until pliable.

4. Add assembled rice balls to boiling water, and gently stir to prevent balls from sticking to one another and bottom of pot. Cook, gently stirring occasionally and adjusting heat as necessary to maintain a gentle boil, until rice balls expand slightly and rise to the surface and skin of rice balls appears almost translucent, about 15 minutes. Meanwhile, repeat step 3 with remaining dough portion and remaining 16 chilled sesame balls.

5. Using a slotted spoon, remove cooked balls from water, and transfer to a large heatproof bowl; pour 1 1/2 cups boiling water from pot over balls to keep warm.

6. Repeat steps 4 and 5 using remaining assembled rice balls. Discard remaining boiling water in pot. Bring remaining 6 cups water to a gentle boil in a separate large pot over high. Add lump sugar; cook, stirring constantly, until sugar dissolves, about 2 minutes.

7. Spoon 4 rice balls into each of 8 small serving bowls. Ladle sweet soup evenly on top.

Notes

Find opaque white lump sugar and sweet glutinous rice flour at Chinese grocery stores or online.