To prepare the vinaigrette, add shallot, garlic, harissa, tomato, lemon, cumin, coriander, salt, pepper, parsley, honey and 2 tablespoons water to a blender. 

Blend on medium speed for 2 minutes, then slowly drizzle in olive oil with machine running. 

Taste and adjust seasoning, thinning out dressing with more water if desired. 

Transfer to a bowl, cover and chill for at least 1 hour.

To prepare the salad, preheat a grill to high heat. 

Toss eggplant slices with 2 tablespoons of the olive oil and season with salt and pepper. 

Grill each slice for about 3 minutes on each side, turning once. 

Transfer to a bowl large enough to hold all the vegetables. 

Toss peppers in another tablespoon of olive oil and season with salt and pepper. 

Grill peppers for about 3 minutes on each side and add to bowl with eggplant. 

Toss onion slices in remaining tablespoon of olive oil, season with salt and pepper and grill for about 3 minutes per side. 

Add to bowl with peppers and eggplant. 

Cover and let vegetables sit for about 20 minutes. This will allow them to finish cooking through. 

Uncover and let cool to room temperature.

To assemble salad, toss greens with parsley leaves and arrange in a large salad bowl or on a platter. 

Arrange the grilled vegetables and chickpeas in sections over the greens. 

Arrange couscous in the middle and top with black olives. 

Stir dressing to recombine and serve alongside salad.