Preheat oven to 180°C. Put the aubergine and garlic bulb (unpeeled and as whole) on a baking tray and roast for 30- 35 minutes until they are soft.
Cool them for 10 minutes, then scoop out the aubergine flesh. Pop out the garlic flesh of about 6 cloves of garlic (about half a bulb). Use the rest for other dishes.
Put the aubergine flesh, garlic pulp, lemon juice, tahini, oil, salt and pepper in a small food processor. Add most of the herbs. Blitz for a few seconds until you get a smooth or slightly textured purée. Transfer to a serving dish.
Drizzle with a drop of oil and garnish with the remaining herbs. Serve immediately or cover and chill until serving.