Preheat the oven to 425 degrees F. Scrub the sweet potatoes and poke them each with a fork a few times. Spray or brush with olive oil and place them on a baking sheet.
Roast the potatoes for 45 to 55 minutes, until super tender inside. Let cool until easy to touch.
While the potatoes roast, heat the beef in a skillet over medium heat. Season all over with salt and pepper.
Cook until browned, breaking it apart into small crumbles. Stir in the ketchup and mustard until combined. Turn off the heat and add in a sprinkle of cheese - just an ounce or two. Let the beef cool slightly.
When the potatoes are ready, slice them down the center. You can use a fork to gently mash some of the potato inside if you wish. Top each potato with a few spoonfuls of the ground beef (or as much as you want!) and the shredded cheese. Drizzle with the house sauce.
Stick the potatoes back in the oven so the cheese can melt, about 5 to 10 minutes.
Remove from the oven and top with all the toppings! More house sauce, lettuce, tomato, pickles and pickled onions. YUM.