Stir together mayonnaise, cheese, mustard, 1 clove of minced garlic, lemon juice and black pepper together in a small bowl. Stir in 3 tablespoons of water and add more water if necessary to achieve desired consistency.
Cover and chill the sauce for 30 minutes in the refrigerator. Taste and adjust the sauce if desired - adding more garlic, black pepper or water.
Serve as a dip or as a salad dressing. Keep in an airtight container in the refrigerator for up to 3 days.