Begin by cooking the rice according to package instructions and set it aside to cool.
In a mixing bowl, whisk together the buttermilk and egg. In another bowl, season flour with salt and pepper. Place panko breadcrumbs in a third bowl.
Dip each piece of chicken in the flour, shaking off excess. Then, dip in the buttermilk mixture and finally coat with panko breadcrumbs.
Heat vegetable oil in a large skillet over medium-high heat. Once hot, add the breaded chicken pieces in batches, frying until golden brown and cooked through, about 4-5 minutes per side. Remove from skillet and place on a paper towel-lined plate to drain excess oil.
In a small bowl, mix together the mayo, sweet chili sauce, and sriracha until well combined to create the Bang Bang sauce.
In serving bowls, layer the cooked rice with broccoli, shredded carrots, and green onions. Top with crispy chicken and drizzle generously with the Bang Bang sauce.
Garnish with sesame seeds if desired and serve immediately.