Step 1In a medium bowl, whisk together yolks, lemon juice, and mustard. While whisking add a few drops of oil at a time, then as it starts to thicken, add oil in a slow steady stream.
Step 2Stir in garlic, parsley, dill, and chives. Season with salt, pepper, onion powder, and a pinch of cayenne, then add milk. If ranch is too thick, add milk a tablespoon at a time to thin.