Finely chop the cilantro and grate or press the garlic. Zest and juice the lime.
In a small bowl, combine sour cream, mayonnaise, lime juice, zest, garlic, salt, pepper, and MSG. Stir until smooth and creamy. Add water, one tablespoon at a time, until the sauce reaches your desired consistency.
Add more lime juice for extra tang or cilantro for a stronger herby note.
Let the sauce sit in the fridge for at least 15 minutes, it helps the flavors come together beautifully.
