Cut the chicken into 1 inch chunks.
In a medium sized mixing bowl whisk the eggs together then add the chicken to the bowl with the eggs making sure the chicken is fully coated in the egg.
To a large mixing bowl, add the gluten free flour and the tapioca flour and whisk together.
Using a slotted spoon or tongs, carefully add the egg coated chicken to the mixing bowl with the flour. Be sure to shake off any excess egg and mix the chicken until it's fully coated in the flour.
To a large skillet add the avocado oil and heat to medium heat. In a single layer, add the chicken to the heated pan and cook for 5-6 minutes a side.
While the chicken is cooking, chop the red bell pepper, green bell pepper, and onion. Also, mince the garlic.
Once the chicken is cooked and golden brown, remove it from the skillet and set aside.
In the same pan you cooked the chicken, add the onions, red bell peppers, and green bell peppers. Saute them for about 5 minutes or until the onions just start to soften. Then add the garlic and saute for 60 seconds. If you're adding pineapple then add it with the garlic.
In a small bowl, whisk together the ketchup, the coconut aminos, the coconut sugar, and the vinegar. To the bell peppers and onions, add the sauce and cook on medium low heat for 2 minutes.
Add the cooked chicken pieces back into the skillet and gently stir to coat the chicken in the sauce.
Optional: serve with a sprinkle of sesame seeds and green onions.