Cut the eggplants in half lengthways and place the four eggplant halves, flesh-side up, onto the baking sheet. Brush the flesh completely with oil. Place into the oven to roast until tender and easily pierced with a knife, about 35 minutes.
While the eggplants are roasting, place a frying pan on medium heat. Add in the oil. When the oil begins to shimmer, add the chopped onions and cook until soft and translucent approximately 2-3 minutes. Add the garlic and cook 2 minutes more until the garlic is soft.
Add in the spices except paprika and cook for 1-2 minutes stirring constantly until the spices are fragrant. Mix in the black beans and cook on low for 4-5 minutes. Stir in the paprika and remove from heat. Set aside until the eggplants are roasted.
Assemble the Eggplants
Place the roasted eggplant halves onto a serving dish. Spoon all the back bean mixture on top of each half. Drizzle with Tahini Sauce and garnish with chives, walnuts and tomatoes.