Preheat the oven to 425 degrees.
Line a large rimmed baking sheet with parchment paper or aluminum foil and then set aside.
In a food processor, crush cereal until it measures 1 cup.
Combine ground cereal with cumin and place in a shallow bowl.
In another shallow bowl, stir together the flour, salt, and pepper.
In a third shallow bowl, lightly beat the egg whites with 2 tablespoons of water until combined.
Dip the sweet potato first in the flour mixture, shaking off excess. Then dip each wedge into the egg white mixture until coated. Finally, dip the sweet potato in the cereal mixture, pressing the exposed surface of the potato into the cereal. Transfer potato wedges onto the prepared baking sheet as you go.
Bake potatoes until tender and crisp, about 25 minutes, turning once.
While the potatoes are in the oven, combine the mayonnaise and harissa for the dip. Add additional harissa if you prefer your aioli spicy.
When the potatoes are done, sprinkle with additional salt, if desired. Serve warm with harissa aioli and sprinkled with chopped fresh cilantro.