Preheat the oven to 375 degrees Fahrenheit. Using a fork, poke holes in the sweet potatoes and place them on a baking sheet. Bake for about 60 minutes, until a fork can easily pierce the inside.
While the potatoes bake, make the Thai Peanut Sauce. Pour half of the peanut sauce in a shallow dish and toss with the cubed tempeh.
When potatoes are ready, remove from oven and set the oven to broil. Slice each potato down the middle and allow to cool for 10 minutes. Gently spoon out the inner flesh from each potato. Leave a wall of 1/4-1/2 inch of sweet potato around the skin for support. Place roughly 2/3 of the soft flesh in a small bowl. The remaining can be frozen or discarded. Add coconut milk, curry paste, and lime juice. Whip the mixture together using a handheld mixer.
Fold in red bell pepper mixture, scallions, cilantro, peanuts, and seasonings. Spoon filling back into each sweet potato and return to the oven until tops have browned (about 3 minutes).