Cut the eggplant in half lengthwise and rub with some salt and 2 Tbsp oil.
Place in a roasting dish with garlic and bake at 180°C for 15-20 mins.
Remove from the oven and allow to cool.
Put eggplant and roasted cloves of garlic into a food processor with the yoghurt, tahini, the remaining oil and lemon juice. Blend to a smooth consistency. Season with salt and pepper.