Begin heating a large skillet over medium heat. Place 1/2 cup cornstarch in a large bowl. Beat eggs in a separate large bowl. Place bowls side by side close to stove.

When skillet is hot add oil. Season all the chicken pieces with salt and pepper. Place all in cornstarch and toss to coat. Transfer pieces to egg, shaking off excess cornstarch, and toss to coat again (I think using your hands works best for this step, clean of course).

Arrange half of the pieces in skillet (to prevent crowding and sticking together). Cook until golden brown on all sides and cooked through. About 7 minutes. Transfer to a paper towel lined plate. Repeat with remaining chicken.

If adding veggies place in skillet after chicken is removed. Cook until they begin to soften, about 5 minutes, stirring often. (My husband prefers without, so I leave out the peppers, but I won't budge on the onion. Lol.)

While chicken or veggies cook, wisk together reserved pineapple juice, chicken broth, vinegar, brown sugar, ketchup, soy sauce, and 2 tbs cornstarch (and red pepper flakes if using).

Add sauce to skillet. Bring to a simmer and cook until thickened, stirring often. Add chicken and pineapple tidbits to sauce. Stir to coat. Reduce heat to medium-low and cook until warmed through.

Serve over rice, garnish with green onion/scallions if desired. Enjoy!