For the Cauli Mash: steam or boil about 1.25 cups cauliflower. Drain (reserving a little water) and puree in blender or food processor. Can also blend thawed frozen cauliflower, which as already been steamed or par-boiled.
Preheat oven to 375F.
Combine all ingredients in a large bowl and mix well, either with your hands or using a stand mixer.
Scoop out medium-sized meatballs (I usually use the small or medium scooper in my 3-scoop set.) You should get about 16 meatballs.
Place them on a parchment or silpat-lined baking sheet and bake about 18 minutes. You can also just check the temperature with a thermometer; you want the centers to be at 165ºF.
Notes
Onions can be sautéed ahead of time or not - I haven't really noticed a huge difference in flavor. To Fry: Warm a large deep-sided pan or cast-iron skillet over medium-high heat. Add enough ghee, coconut oil, avocado oil, or other fat of choice to cover the bottom of the pan, then fry each meatball, turning as much as needed to cook on all sides. You will have to do this in batches and it will likely spatter a little! Be sure to check doneness.