On the large holes of a box grater, grate the tempeh. Set aside.
In a small bowl combine chili powder, cumin, corn starch, salt, onion powder, garlic powder, ground coriander, and ancho chili powder. Add the tomato paste and water and mix thoroughly. Set aside.
Heat 2 tablespoons olive oil in a large pan over medium heat. Once hot, add the onions and peppers. Cook, stirring frequently, 3-4 minutes until softened. Add the grated tempeh and spice mix and stir to coat everything in the spices. Allow to cook, stirring occasionally, until heated through.
Meanwhile, heat 1 teaspoon olive oil in a large skillet over medium heat. Once hot, add a corn tortilla and swirl it around in the oil. Let cook 1-2 minutes per side or until beginning to char and crisp. Remove from the pan, add more oil as necessary, and continue with as many tortillas as desired.
To assemble the tacos, add a spoonful of the tempeh mixture topped with avocado, cabbage, cilantro, lime juice, and radish salsa.