In a non-toxic (non-teflon) skillet, heat the coconut oil over medium-high heat. Add the onions and garlic and cook for about a minute.
Add the blackberries and let break down (about 1–2 min). Pour in the vinegars and stir to combine.
Transfer mixture to a blender or food processor and add the stevia, salt, and pepper. Blend until smooth and add the olive oil slowly with blender or food processor. To remove all seeds, strain through a mesh strainer.
Place the greens on a plate. Put remaining ingredients as desired and drizzle with dressing.
For a nice presentation, put apples, blackberries, walnuts, and turkey in sections around the edges of the green salad.