MARINATE THE RHUBARB (BEGIN 2 HOURS AHEAD):
1. In a small saucepan, combine the sake, sugar, ginger slices, and gochugaru over medium heat. Stir until the sugar dissolves, then remove from heat and allow to cool for 10 minutes.
2. Place the rhubarb batons in a shallow dish in a single layer. Pour the warm sake mixture over them, turning gently to coat. Cover and refrigerate for at least 2 hours, turning once halfway through. The sake mellows the rhubarb's sharpness while the gochugaru adds a gentle warmth.
3. When ready to serve, preheat the oven to 375°F (190°C). Lift the rhubarb from the marinade (reserve the liquid) and arrange in a single layer on a parchment-lined baking sheet. Roast for 8-10 minutes until just tender but still holding its shape. The batons should yield to gentle pressure without collapsing.
4. Meanwhile, simmer the reserved marinade in a small saucepan over medium heat until reduced to a light syrup, about 3-4 minutes. Discard the ginger slices. Set the syrup aside.

COOK THE JASMINE RICE PUDDING:
5. Rinse the jasmine rice under cold running water until the water runs mostly clear, about 30 seconds. Drain well. This removes excess surface starch while preserving the natural fragrance.
6. In a medium heavy-bottomed saucepan, combine the rinsed rice, coconut milk, whole milk, sugar, and salt. Add the bruised lemongrass stalks, star anise, and crushed cardamom pods directly into the liquid.
7. Bring to a gentle boil over medium heat, stirring occasionally. As soon as it begins to bubble, reduce the heat to the lowest possible setting. Cover with a lid slightly ajar and cook for 25-30 minutes, stirring every 5 minutes to prevent sticking on the bottom.
8. The pudding is ready when the rice is completely tender and the mixture is thick and creamy — it should coat the back of a spoon and fall in lazy ribbons. If it thickens too quickly before the rice is fully cooked, add a splash of milk and continue cooking.
9. Remove from heat. Fish out and discard the lemongrass stalks, star anise, and cardamom pods. The pudding will thicken further as it sits. Cover and keep warm, or cool and gently reheat with a splash of milk before serving.

MAKE THE COCONUT AND SESAME BROWN SUGAR CRUMB:
10. Preheat a dry skillet over medium-low heat. Add the shredded coconut and toast, stirring constantly, until golden with deep amber edges, about 3-4 minutes. Transfer to a bowl immediately — coconut burns quickly.
11. In the same skillet, toast the sesame seeds, stirring constantly, until golden and fragrant, about 2 minutes. Add to the bowl with the coconut.
12. Add the brown sugar, melted butter, and salt to the toasted coconut and sesame. Stir to combine into a loose, sandy crumb. Spread on a plate to cool and crisp. The crumb should remain loose and crunchy, not clumped.

PREPARE THE MANGO:
13. Toss the diced mango with the lime juice and a pinch of gochugaru. The lime juice brightens the natural sweetness while the chili echoes the warmth running through the rhubarb.

ASSEMBLE AND SERVE:
14. Spoon a generous portion of warm rice pudding into shallow serving bowls — make the pudding the star, as Marcus recommended.
15. Arrange 3-4 roasted rhubarb batons alongside the pudding, slightly overlapping. Scatter the seasoned mango dice over and around the dish.
16. Drizzle a teaspoon of the sake reduction syrup over the rhubarb and pudding.
17. Sprinkle the coconut-sesame brown sugar crumb over the top for textural contrast. Finish with a few fresh coconut shavings and, if desired, a small mint leaf.