Bake Sweet Potatoes: Preheat oven to 425 degrees. Thoroughly clean the sweet potatoes and remove any dirt or grit. Prick the sweet potatoes all over with a fork and place them on a sheet pan lined with parchment paper. Bake the sweet potatoes for 45-50 minutes until completely tender. You should easily be able to stick a skewer of toothpick into the thickest part. Once the potatoes are tender, remove them from the oven.
Make the Sloppy Joe Sauce: Add all of the sauce ingredients to a mixing bowl and whisk together until well combined. Set aside.
Make the Sloppy Joe Mixture: Heat a large skillet over medium-high heat. Once hot, add the avocado oil and then add the ground beef. Brown the ground beef until no longer pink, breaking it up as it cooks.
Once the meat is brown add the diced onion, garlic, and bell pepper to the skillet along with a pinch of salt and black pepper. Continue to cook for 3-5 minutes until the onion is tender and translucent.
Next, lower the heat to low and pour in the sloppy Joe sauce. Stir until well combined and let simmer on low for 10-12 minutes. The sauce should thicken a bit as a it simmers.
Assemble: When you are ready to serve, use a sharp knife to split the top of the potato open lengthwise. Give the potato ends a gentle squeeze inward to open it up a bit and use a fork to fluff the insides a bit. Top each potato with a generous spoonful of the sloppy joe mixture. Top with sliced green onion and, if using, shredded cheddar cheese.