In a medium bowl, place the cubed tempeh.
Into a blender or food processor, place 3/4 cup of the cashews, the garlic, vinegar, soy sauce, cinnamon, turmeric, cumin, and chili powder. Pulse, adding water as needed to achieve a texture slightly thinner than peanut sauce. Pour over the tempeh. Set aside.
Dice the carrots, seed and slice the red and yellow peppers into strips, and de-stem and chop the kale. Finely chop the remaining 1/4 cup cashews.
In a large skillet or wok over medium heat, heat the oil. Drain the tempeh, reserving the sauce. Add the tempeh to the skillet and stir-fry until it begins to brown, 4 to 6 minutes. Add the vegetables and stir-fry until the kale has brightened and the carrots are tender, 3 to 5 minutes.
Pour in the reserved sauce and cashews, stir to combine, and serve.