Preheat your oven to 350.
Dice your sweetpotatoes and add to a baking sheet. Combine olive oil and spices in a bowl and add to diced sweetpotato.
Cook for 25-30 minutes, or until sweetpotatoes soften.
While the sweetpotatoes are baking, add all ingredients to a blender or food processor and blend.
Taste and adjust as necessary (more/less salt, more lemon, cheese, etc.)
Pour pesto onto sweetpotatoes and enjoy.
An alternative way to make this is to microwave sweetpotatoes for 5-7 minutes, until cooked through. Let them cool, add some butter and top with pesto.