Preheat oven to 400 degrees. Stab sweet potato with a fork a couple times to give it ventilation.
Bake sweet potato for 40 to 60 minutes, depending how big it is. Take it out when it is soft and tender. Leave oven on.
While sweet potato bakes, boil chicken breast if needed to make shredded chicken. Chop red onion into slivers, and cilantro if using.
When Sweet potato is cooked and cooled slightly, slice in half (length-wise) and open. Cover with parchment paper and press a skillet down on top to flatten (with skin on the bottom). You are looking to get a 1/2 inch thick pizza-shaped crust.
Season crust with salt and pepper and a little touch of olive oil. Place back int he oven for about 10 minutes.
Once crust has cooked slightly, top with BBQ sauce, shredded chicken, red onions, mozzarella, and cilantro. Put back in oven for 5-10 minute, until the cheese has melted.
Take out, let cool slightly, and enjoy.