Cut the chicken into 1-inch pieces. In a mixing bowl, combine the chicken with coconut aminos, mirin, salt, pepper, grated ginger, egg whites, and cornstarch. Toss to coat evenly, then let marinate for at least 30 minutes or up to 3 hours.
While the chicken is marinating, prepare the sauce ingredients. In a mixing bowl, combine the honey, coconut aminos, chicken stock, rice vinegar, ginger, garlic and red pepper flakes. In a separate bowl, prepare the cornstarch slurry by mixing the cornstarch with water.
In a large skillet, heat enough oil over medium-high heat to coat the bottom of the pan. Once hot, add the chicken pieces in a single layer—being careful not to overcrowd the pan. Cook in batches if needed. Sear the chicken for 3–4 minutes per side, until golden brown and cooked through. Transfer to a wire rack or a paper towel-lined plate to drain. Discard the used oil and wipe the skillet clean.
To the skillet, pour in the honey ginger sauce mixture and bring it to a gentle simmer. Stir in the cornstarch slurry, mixing continuously until the sauce thickens. Add the cooked chicken and toss until each piece is fully coated in the sticky, flavorful sauce.
Serve over white rice and your favorite stir-fry vegetables. Enjoy!