First, make the aioli. In a bowl, mix the chickpea liquid (60ml) with the juice of half a lemon, two finely chopped garlic cloves and 1 teaspoon of mustard. Grind/beat with a hand blender or hand mixer until fluffy. Pour the oil (250ml) while mixing, until mayonnaise forms. The more oil you add, the thicker it gets. Season with salt and pepper.
You can keep the leftover chickpeas in the fridge for at least 2 days. Make hummus and freeze it, or use it in a salad with, for example, boiled beets, capers, dill and Garden Gourmet balls, or grilled pieces.