Prick each sweet potato a few times with a fork and brush all over with olive oil. Arrange on a baking sheet and bake until tender, about 40 minutes.
While the sweet potatoes bake, cook the bacon in a skillet over medium heat until browned and crisp, about 15 minutes. Use a slotted spoon to transfer the bacon to a paper towel–lined plate to drain.
Stir together the beans, cheese and bacon. Set aside.
When the sweet potatoes are tender, carefully cut them in half lengthwise and arrange, cut side up, on the baking sheet. Using a spoon, scoop out some of the flesh and transfer to a bowl (reserve for another use).
Divide the bean mixture evenly among the sweet potato boats. Return to the oven and bake until the filling is hot and bubbling, about 10 minutes.
Top the boats with the salsa, avocado, radishes and cilantro and serve at once.