Preheat the oven to 400˚F. Line a baking sheet with parchment paper.
Toast the panko in a dry skillet over medium heat until light golden brown. Let cool.
Cut the chicken into 1-inch pieces. Place the mayonnaise in a mixing bowl, add the chicken, and toss well to coat. Toss the chicken in the toasted panko making sure to coat well. Place on the prepared baking sheet, spacing pieces apart. Spray with cooking spray and cook for 15 minutes.
While the chicken cooks, prepare the sauce. Combine the soy sauce, honey, ketchup, brown sugar, rice vinegar, sesame oil, and cornstarch in a mixing bowl and whisk well.
Heat the vegetable oil in a large pan over medium heat. Add the garlic and cook for 30 seconds. Add the soy sauce mixture and bring to a simmer. Cook until heated through and thickened, 3-4 minutes. Add the chicken, stir to coat. Garnish with sesame seeds and green onions and serve over rice.