Mix together the ingredients of the marinade in a medium bowl. In a second large bowl, add the tempeh and onion and pour the marinade over -making sure to toss and cover all pieces. Cover and refrigerate over night or at least 3 hours.
Cook grain according to package directions and have warm when ready to serve.
When ready to cook, heat a tablespoon of extra virgin olive in a large skillet over medium high heat and then add the marinated tempeh and all additional liquid. Cook for 5-7 minutes or until the majority of the liquid has cooked off. Add kale and cook for 4 additional minutes -making sure to actively stir the dish.
When ready to serve, serve the tempeh over the grain and add avocado to garnish. Season with sriracha or chili paste for an added spicy kick!