Make the sauce: In a small saucepan combine the orange juice, brown sugar substitute, white vinegar, soy sauce, and minced garlic. Heat over medium until it begins to simmer, about 3–4 minutes.
If using xanthan gum, sprinkle it into the simmering sauce and whisk vigorously until fully incorporated and the sauce thickens, about 1–2 minutes; continue to simmer 2–4 more minutes until sticky.
Prepare chicken coating: In a large bowl whisk together the eggs and heavy cream, then add the chopped chicken and stir to combine.
On a large plate mix the coconut flour, salt, and pepper to make the dry coating.
Coat the chicken: Working one piece at a time, dip each chicken piece from the egg mixture, then roll it in the coconut flour mixture until evenly coated.
Heat the oil in a large frying pan or skillet over medium heat until hot (about 350°F/175°C). Fry the coated chicken in batches without overcrowding the pan, 2–3 minutes per side or until golden and cooked through. Use tongs or a slotted spoon to transfer cooked pieces to a paper-towel-lined plate.
When all chicken is cooked, place the fried pieces in a bowl, pour the warm orange sauce over them, and toss until evenly coated.
Serve immediately while the chicken is hot and the sauce is sticky.
