Preheat your oven to 450°F / 230°C. On a large rimmed baking sheet, toss the eggplant cubes with 1½ tablespoons of olive oil, ¼ teaspoon of salt, and ¼ teaspoon of pepper.
Spread them in a single layer and roast for 20 minutes.
Stir the eggplant, then roast for another 10 minutes until tender and beautifully browned.
Let cool completely on the baking sheet.
While the eggplant roasts, bring a large pot of salted water to a boil.
Add the bulgur and cook for 4 minutes.
Stir in the rinsed quinoa and continue to boil for about 12 minutes, or until both grains are tender yet still have a slight bite.
Drain well and transfer to a large serving bowl to cool, fluffing occasionally with a fork.
Once cooled, stir in the chopped mint, cilantro, cooled roasted eggplant, and halved grape tomatoes.
In a separate medium bowl, whisk together the lemon juice, the remaining 2 tablespoons (30 ml / 1 fl oz) of olive oil, ½ teaspoon of salt, and ½ teaspoon of pepper to create the dressing.
Add the chickpeas and finely chopped red onion to the dressing and let them marinate for at least 15 minutes to absorb the flavors. Gently fold the marinated chickpea mixture into the grain and eggplant salad.
Garnish with fresh mint sprigs before serving.
Add herbs last. For the brightest flavor and color, fold in the fresh mint and cilantro just before serving, especially if you're making the salad ahead of time.
