If using canned chickpeas: drain and rinse well. (Optional) For extra silkiness, peel some skins by rubbing chickpeas between your fingers or a towel. If using cooked-from-dry chickpeas: reserve ½–1 cup cooking liquid.
In a food processor, add the tahini and 2 tbsp lemon juice. Process 30–45 seconds until pale and loosened.
Add the garlic, salt, and cumin (if using). Pulse to combine and taste the tahini mixture — it should be bright and slightly tangy.
Add half the chickpeas and process until mostly smooth. Scrape down the sides, add the remaining chickpeas, and process again.
With the processor running, stream in 2 tbsp olive oil, then add cold water or aquafaba, 1 tbsp at a time, until the hummus reaches a silky, spreadable consistency. If you want ultra-light texture, add an ice cube while blending and remove it before finishing.
Taste and adjust: more salt for lift, more lemon for brightness, or another small garlic clove if you want more bite.
Transfer to a shallow serving bowl. Create a shallow well with the back of a spoon, drizzle extra-virgin olive oil, and finish with smoked paprika or sumac, chopped parsley, and optionally toasted pine nuts or a few whole roasted chickpeas.
Serve at room temperature with warm pita, veggies, or as desired.