Prepare the vegetables: Preheat the oven to 400°F (200°C), or 350°F (180°C) fan. Pierce each whole eggplant several times with a fork. Slice the top from the garlic bulb to expose the cloves, keeping the bulb intact.
Arrange the tray: Place the eggplants, garlic cut side up and cherry tomatoes in a large roasting dish. Use 1 tbsp of the roasting oil to coat the eggplants and drizzle over the exposed garlic. Toss the tomatoes with the remaining 1 tbsp roasting oil and the ¼ tsp salt. Leave the dish uncovered.
Roast until tender: Roast for approximately 50 to 60 minutes, checking the tomatoes after 25 to 30 minutes. Lift the tomatoes into a bowl once blistered and soft but still holding some shape. Remove the garlic when the cloves are completely soft. Continue roasting the eggplants until collapsed and tender all the way through; larger vegetables may need longer. If the garlic browns too quickly, loosely cover just the bulb with a small piece of foil.
Cool and chop: Let the eggplants and garlic cool for about 15 minutes, or until safe to handle. Scoop out the eggplant flesh and discard the skins and stems. If the flesh is visibly watery, let it drain in a strainer for 5 to 10 minutes. Finely chop it with a knife.
Mix the dip: Squeeze the soft garlic cloves into a bowl and mash well. Stir in the chopped eggplant, tahini, lemon juice and ½ tsp salt. Taste and adjust the lemon and salt as needed.
Dress the tomatoes: Gently mix the roasted tomatoes with the balsamic glaze and parsley, keeping some tomatoes whole.
Plate and serve: Spread the dip across a shallow serving plate. Spoon the tomatoes and a little of their juices down the center, leaving excess liquid behind. Drizzle with the final 1 tbsp olive oil and serve with bread.
Notes
Doneness: Soft flesh matters more than the clock. Roast longer if the eggplant has firm patches or the garlic cannot be mashed easily.Texture: Chop by hand and drain only if watery. Keep the tomato topping separate until serving.Storage: Refrigerate the dip and tomatoes in separate airtight containers within 2 hours and use within 3 days.