Microwave 2 medium sweet potatoes until just softened, 6 to 7 minutes. Let cool slightly, then trim off the ends and slice into 1/4- to 1/2-inch-thick rounds.
Cook 6 bacon slices in 1 tablespoon vegetable oil in a large skillet over medium heat until crisp, about 12 minutes; drain on paper towels and break into pieces. Combine 1 tablespoon bacon drippings with 1/3 cup mayonnaise; season with salt and pepper. Cook the sweet potato rounds in the remaining drippings (add more oil to the pan if needed), turning, until crisp, 15 to 20 minutes. Drain on paper towels and season with salt.
Top each sweet potato round with some of the mayonnaise, a small piece of lettuce, more mayonnaise, jarred sun-dried tomato bruschetta topping and the bacon.