Add the ingredients for the sauce to a small blender and blend until completely combined (I use my Magic Bullet). If you don’t have a small blender, you can simply stir everything well in a bowl - just be sure to mince the garlic and grate the ginger. Set the sauce aside until ready to use.
Whisk the egg until well-beaten in a mixing bowl. Chop the chicken and transfer it to the bowl with the egg. Stir well until the chicken is well-coated in egg. Add the flour and stir everything around until the chicken is coated in flour as well.
Heat the avocado oil in a large (12-inch) skillet over medium-high heat. Once the skillet is hot, add the chicken and spread it into an even layer. The chicken pieces will want to stick together - don’t worry about it, they’ll come apart as you continue cooking.
Allow the chicken to brown, stirring every couple of minutes, until the pieces have a nice golden-brown crust to them (you don’t need to cook the chicken through just yet).
Pour in the sauce and stir well. Bring the mixture to a full boil, then cover the skillet and reduce the heat to medium. Allow the chicken to cook, stirring occasionally, until chicken is cooked through and the sauce is thick and sticky, about 5 to 8 minutes.
Serve orange chicken with choice of steamed or fried rice and enjoy!