Roast sweet potatoes: Preheat oven to 400°F. Cut sweet potatoes in half, rub with olive oil and salt. Place cut-side down on a baking sheet. Roast 30 minutes, until caramelized and fork-tender.
Cook sloppy joe base: Heat 1 Tbsp olive oil in a large skillet over medium-high heat. Add diced onion and bell pepper, sauté 3–4 minutes. Add ground meat and cook until no longer pink.
Add sauce: Stir in garlic powder, mustard, ketchup, tomato paste, chili powder, vinegar, paprika, coconut aminos, pepper, and salt. Simmer 5–10 minutes until thickened.
Make the coleslaw: Mix all of the ingredients for the coleslaw together and set aside.
Assemble bowls: Place one roasted sweet potato half in each bowl. Top with 1 cup coleslaw mix, 1 cup sloppy joe mixture, and pickled onions if desired.
Serve or store: Serve immediately or store in the refrigerator up to 4 days for meal prep.