Cut chicken into 1 ½" cubes and pat dry. Place cubed chicken in a large bowl and sprinkle with cornstarch and garlic powder. Toss to fully coat the chicken.
In another bowl, add egg and whisk. Pour egg on top of the chicken and toss to coat.
In the last bowl, add breadcrumbs. Working with each piece of chicken, dip into breadcrumbs on both sides to fully coat. Repeat with all chicken nuggets and transfer to parchment paper lined baking sheet.
Place chicken nuggets in the oven and bake for 15 minutes. Carefully flip chicken over and bake for another 10 minutes.
While the chicken is baking, whisk together melted butter and buffalo hot sauce. When the chicken is done baking, toss chicken into the buffalo sauce and toss to fully coat chicken.
Serve Buffalo Chicken Nuggets with homemade ranch dressing. Enjoy!!