Heat the avocado oil in a large skillet (a large 12-inch skillet with a deep rim is recommended!) or a large pot over medium-high heat.
Add the sliced onion and cook until the onion has softened, about 5 minutes.
Transfer the sliced cabbage to the skillet, stir as best you can (it will be overflowing) and cover with a lid. Cook, stirring occasionally, until the cabbage has wilted and much liquid is seeping out, about 10 to 15 minutes.
Remove the lid and create space in the center of the skillet to add the ground turkey and the garlic. Allow the turkey to brown for a few minutes untouched, then use a spatula to break it into smaller pieces and incorporate it into the cabbage and onion.
Pour in the coconut aminos (or liquid aminos or soy sauce) and stir well.
If there is still a lot of liquid at the bottom of the skillet, continue cooking over high heat, stirring occasionally, until the sauce has thickened to your desired level of thickness.
Serve this ground turkey cabbage skillet with any choice of side dishes and your favorite toppings (such as grated cheese, sliced avocado, hot sauce, salsa, sour cream, etc). And enjoy!