In a large bowl, stir together the mashed sweet potato, nut butter, maple syrup, and vanilla until smooth and cohesive.
Fold in oats, flaxseed, cinnamon, nutmeg, ginger, cloves, and salt. Mix until a thick dough forms. If it's too sticky, add 1–2 extra tablespoons oats.
Fold in chocolate chips or pecans if using. Don't be shy—texture is life.
Pop the bowl into the fridge for 15–20 minutes. This firms the mixture and makes rolling less messy.
Scoop tablespoon-sized portions and roll into 18–22 balls, depending on preferred size. If desired, roll in graham crumbs, coconut, or a cinnamon sprinkle.
Place on a parchment-lined tray. You can eat immediately, but 30 minutes in the fridge helps them set like champs.