Zest a lime with a zester or fine grater until you have 1 teaspoon of zest, then cut the lime and squeeze out 1 tablespoon of juice, removing any seeds.
Peel and crush 1 clove garlic (use a garlic press or mince finely and press with the side of a knife until pasty).
In a bowl, add 8 oz sour cream, the crushed garlic, 1 teaspoon lime zest, 1 tablespoon lime juice, and 1/4 teaspoon salt.
Whisk the mixture until smooth and evenly combined.
Taste and, if desired, adjust the salt, garlic, or lime to your preference by adding small amounts at a time; serve immediately or chill before serving.
Notes
You can use¼teaspoon of dried garlic granules instead of fresh garlic.