Soak the bite-sized chicken pieces in the buttermilk for a minimum of 15 minutes.
In a separate shallow bowl, whisk together the cornstarch, flour, garlic powder, paprika, salt, and pepper to create the coating.
Dredge the marinated chicken through the flour mixture, shaking off any excess.
Heat about 1 inch of vegetable oil in a pan over medium-high heat, then fry the coated chicken in batches for 3–4 minutes per side until golden and fully cooked. Drain the crispy chicken on paper towels or a wire rack.
In a small bowl, combine the mayonnaise, sweet chili sauce, sriracha, honey, and rice vinegar. Whisk until smooth.
Just before serving, toss the hot, crispy chicken with the bang bang sauce until coated.
Divide the cooked rice, mixed greens, sliced cucumber, and carrot between two serving bowls.
Top the bowl base with the sauced chicken.
Garnish with fresh chopped cilantro and a lime wedge.