Edit 8 June 2021: So when I originally wrote this about three years ago, I was using an *extremely* crappy food processor. I now have a sort of Nutribullet knockoff and it grinds the ingredients to a superb consistency without the extra faff of doing things little-by-little. Both methods are presented below, depending on your device.
I finally cracked it. The madness is in the method. To make good hummus using one 14.5oz/400g can of chickpeas, see instructions below depending on your device.
Related, the Super Kim can opener by Nogent is the only can opener that should exist.
With a high-powered blender or food processor
If you’ve got a food processor or blender that really obliterates everything in its path, you might be able to get away with putting it all in at once. If you do this, you’ll want to add less garlic because you aren’t giving the garlic the chance to mellow out with the lemon juice first.
In a blender, combine 1 can of chickpeas, 4 tbsp fresh lemon juice (from 1 medium-sized lemon, roughly), ½ clove (or one very small clove) of garlic, 4 tbsp tahini, 4 tbsp water, ½ tsp sea salt, and a good pinch of ground cumin (optional).
Blend it all together until very smooth, at least 40 seconds at a pretty high power. Scrape down the sides and blend again if some of the ingredients get stuck. Taste the mixture and add more salt, water, or lemon juice if the taste or consistency isn’t quite as you like.
To serve, drizzle with good quality olive oil and optionally garnish with smoked paprika, za’tar, chopped coriander, toasted cumin seeds, kawarma, extra chickpeas, etc.
With a crappy food processor
If your food processor is not so great, like the tiny food processor attachment that came with my stick blender, you need to break down the steps a bit.
The issue is that the tahini can be a bit “mealy” when it doesn’t get fully emulsified or gets stuck under the blades, and the final texture can be a bit gritty if the chickpeas aren’t soft enough. Some people recommend peeling (!) the chickpeas and while I imagine this helps, it’s not something I’m ever going to realistically do.
Put 4 tbsp lemon juice and 1 clove of garlic in a food processor and blend until the garlic is finely chopped. Let the lemon and garlic sit together in the food processor for a bit during the next step so that the garlic flavor chills out.*
Next, check the firmness of your chickpeas. Some tinned chickpeas are quite soft, most are very firm. (I seem to remember that Tesco’s own brand is weirdly good?! YMMV.) Open and rinse 1 can of chickpeas, then pop one in your mouth. Try to squish it between your tongue and the roof of your mouth. If it doesn’t give super easily, then you’ll want to soften them a bit to get a better final texture.
If you do need to soften your canned chickpeas, dump them in to a pot with enough water to cover and ½ scant tsp baking soda. Bring to a boil and then simmer until they get pretty soft and the skins are separating from the legumes, about 20 minutes. When ready, drain them and allow them to cool. If you want to use them immediately, carefully rinse them in cold water.
Now, add the fats gradually along with a little water. The goal is to emulsify the fat in to the liquid without causing it to separate. Put 4 tbsp tahini in the food processor with the lemon / garlic mixture and blend just until you get a smooth paste. Next add 2 tbsp cold water and blend until very smooth. With the addition of the water, it will get more pale and fluff up a little.
Add your chickpeas, a good pinch of ground cumin, and about ½ tsp sea salt to the food processor and blend until smooth. Taste it and add more salt or lemon juice as necessary. Add a bit of cold water if you like it more fluffy.
To serve, see serving notes in the alternate method above.
* Allicin is responsible for that intense sulfur flavor in raw garlic. Allicin is one of the things that gives garlic its health qualities, but it can also put too much of an edge on some dishes. Mincing or blending raw garlic directly in to lemon cuts denatures allinase, one of the compounds in garlic that creates allicin. Read more about this on The Garlic Farm blog.
Edit 1 09 2020: Increased tahini amount and added baking soda technique inspired by a recipe by Ottolenghi and Tamimi and a Cookie & Kate recipe.