Peel and then shred the sweet potato. You can do this with a box grater or in a food processor. If you want to leave the skin on, you can, just be sure to rinse well before shredding. In a large mixing bowl, combine the sweet potato, TVP, garlic (mince well or press through a garlic press), hot sauce, cumin, and a generous sprinkle of both salt and pepper. Give that a big stir so everything gets combined well. The TVP may seem too crunchy at this stage, but it will absorb some liquid from the sweet potato while it sits in the bowl, and then soften even more when cooked, so don’t worry.
In a large pan, heat 1 tablespoon of oil. Sauté the onion and bell pepper for about 2 minutes over medium heat, until they begin to soften. Add in the sweet potato mix and continue to cook for 8-10 minutes until the potatoes are cooked through. At the 8 minute mark, just give it a taste to see if they seem cooked through to you. If you notice the mixture sticking to the pan too much, add a little more oil, but a few burnt bits are OK for me.
Meanwhile, cook each corn tortilla in a hot pan with a little oil. When we make corn tortillas at family events, my grandma or mother with usually cook them in oil to allow them to float, but I prefer just a little oil and heating them until I see some spots darken on each side and the tortilla is quite soft and bendable. Fill the shells with the sweet potato mix and top with cilantro. Squeeze a little lime juice on just before eating.