Place garbanzo beans in a medium bowl and cover them with a few cups of cold water. Stir in 1/2 teaspoon of baking soda and let soak overnight or for 24 hours.
Drain the garbanzo beans and put them into a medium saucepan. Cover them with water and add the remaining 1/2 teaspoon of baking soda. Bring the chickpeas to a simmer, and cook for 20 minutes, skimming any foam and impurities. Then add 1 teaspoon of salt and continue simmering for about 10 minutes, or until the garbanzo beans are soft and can be easily smashed with a back of a spoon. Remove them from the heat and drain.
Place the garbanzo beans, tahini, lemon juice, and black garlic into a food processor. Sprinkle with a pinch of salt. Process for a couple of minutes until the hummus is smooth. Scrape the sides of the bowl from time to time.
Give your hummus a taste and adjust the seasoning if needed. To make the hummus light and airy, you need to incorporate a bit of ice-cold water. With the food processor running, start adding the water one teaspoon at a time until you get the desired consistency.
Transfer the hummus into an airtight container and drizzle it with some olive oil and cover with a lid. Refrigerate for up to 5 days.