In a medium bowl, whisk together the tahini and minced garlic until combined. The mixture will be very thick and pasty.
Pour in the fresh lemon juice and salt.
Whisk vigorously. The mixture will seize up and become even thicker – don't worry, this is a normal and necessary step!
Slowly stream in the ice-cold water while whisking continuously. The sauce will magically transform, becoming smooth, pale, and creamy.
Continue adding water, one tablespoon at a time, until you reach your desired consistency, similar to a pourable, thick dressing.
Taste and adjust seasoning.
Add more salt for flavor, lemon juice for brightness, or a touch more garlic for a bigger kick.
Serve immediately or store in the fridge.
Don't fear the seize!
When you add the lemon juice, the tahini will thicken dramatically. This is a critical chemical reaction.
Keep whisking and trust the process; the water will smooth it all out.