A few notes: if you can get real buttermilk, it will make this 100 times better. Same goes for Duke's mayonnaise. You'll begin to figure out whether you like this dressing to be runnier and more buttermilk-heavy, or thicker and more like a dip, and adjust the proportions accordingly. We've had amazing success grating lemon zest into this dressing, sprinkling in smoked paprika, etc. It is endlessly customizable. It will keep for a few days in the refrigerator, but be forewarned: the garlic will get more aggressive the longer it sits.