Lay eggplant slices on a grill topper. Brush with olive oil. Season with smoked salt and garlic powder. Grill until browned, about 5 minutes.
Place watercress in a microwave-safe bowl. Heat in the microwave until wilted, about 3 minutes.
Mash white beans in a large bowl. Mix in quinoa. Place a dollop of the mixture in the middle of each eggplant slice. Fold in ends to create 12 parcels.
Top each eggplant parcel with a basil leaf. Divide watercress among parcels.