Preheat the oven to 425°F and arrange the oven rack to the top position. Gently grease a large sheet pan with olive oil or line with parchment paper.
Make the coconut rice. Add the sesame oil to a medium skillet over medium-high heat. Stir in the sesame seeds and cook to toast for 1-2 minutes. Add the rice, coconut milk, water, and salt and stir to combine. Bring it to a boil over medium-high heat. Cover, reduce the heat, and simmer for 15-18 minutes, or until the liquid is absorbed and the rice is fluffy.
Make the meatballs. Add the breadcrumbs to a large bowl and pour the milk on top. Let it sit for 5 minutes. Now is a good time to chop the scallions and garlic. Separate the scallion white from the green ends and mince the white bulb ends. Save the green ends to garnish.
Add the beef to the breadcrumbs along with the scallion whites, ginger, garlic, salt, and red pepper flakes. Use clean hands to mix until well combined.
Use a large cookie scoop to form the meatballs into 1 1/2-inch meatballs. You should have 20-22 meatballs. Place them in a single layer on one side of the prepared baking sheet.
Place the green beans on the other half of the sheet pan in a single layer. Drizzle with 1 Tablespoon olive oil and sprinkle with salt to taste. Toss to coat. Drizzle the remaining 2 Tablespoons of olive oil over the tops of the meatballs.
Bake in the preheated oven on the top rack for 14-16 minutes or until the internal temperature reaches 165°F and the green beans are browned and tender.
Make the sauce. While they’re baking, mix together all of the sauce ingredients in a medium bowl.
Fluff the rice and divide it into bowls. Top with the baked meatballs, green beans, and a generous drizzle of firecracker sauce. Finish with the reserved green onions, extra sesame seeds, red pepper flakes, or chili crunch.