Prepare all ingredients as instructed above.
Rinse the rice and cook according to package instructions. Once tender, season with salt and pepper. Cover and keep warm.
Heat olive oil in a large pot over medium-low heat. Add onion and sauté until softened.
Add chicken and cook for 1–2 minutes. Stir in ginger, garlic, and curry powder. Sauté for 3 minutes.
Pour in 3/4 of the coconut milk and stir. Mix the cornstarch with the reserved 1/4 coconut milk and add to the pot.
Bring to a boil, then reduce heat and simmer until the chicken reaches an internal temperature of 165°F (74°C). Add water if needed to adjust thickness.
Stir in fish sauce (if using), brown sugar, and lime juice. Simmer for 5 more minutes.
Soften each sheet of rice paper in warm water one at a time. Lay flat and layer with butter lettuce, carrots, cucumber, jalapeño, scallions, mint, and cilantro. Roll tightly and set aside.
In a small bowl, whisk together peanut butter, rice wine vinegar, soy sauce, honey, sesame oil, and garlic. Gradually add water until desired consistency is reached.
In a blender, combine banana, maple syrup, vanilla extract, milk, water, and ice cubes (if using). Blend until smooth. Adjust sweetness and consistency as needed.
Serve the Thai yellow curry over rice. Plate with spring rolls and peanut sauce on the side. Pour Korean banana milk into glasses and enjoy.