Start with preparing the aubergine. If you want to grill it after cutting, make sure you drain out the moisture. Cut it longitudinally, sprinkle the pieces with salt and leave it on a sieve to drain. Once the moisture is drained, place it over a foil. 

Rub a little oil over the cut surfaces and place them in the oven to grill. Alternatively, you can grill the whole aubergine over a stovetop or barbeque. Rub the aubergine with oil and grill it whole.

You know the aubergine is grilled when the skin looks charred and the vegetable seems to shrink into itself. Let it cool for 15 minutes and then slowly peel off the charred skin. You will be left with the smoky and cooked flesh. At this point, you can gently squeeze the flesh to drain any moisture. 

You can use a fork to smooth the aubergine pulp into a more homogenous mix. If you want a creamy dip, it is best to use a food processor to blend it. You can also add other ingredients as the machine runs. 

Once the aubergine is broken down, add the garlic, lemon juice, tahini, and oil. Keep an eye on the texture to see that it is not becoming too runny. Add the oil slowly, keeping control over the quantity. 

If you are making it manually with a fork, just add the rest of the ingredients one at a time and use your fork to mix it. 

When serving the baba ghanoush, pour it into a shallow dish. Make a swirly circular pattern with the back of a spoon. You can make a moat of oil around the dip or pour it over the swirls in the dip.