1 small bunch fresh cilantro, chopped
1 clove garlic, peeled, chopped
1 serrano chile, chopped
1 cup sour cream
Salt, to taste
Fresh lime juice, to taste

Blend cilantro, garlic and chile in a blender until smooth. Do not use a food processor. Remove from blender and whisk into sour cream. When well blended, season with salt and lime juice. Pour into a plastic squeeze bottle such as those used for catsup or mustard. Keep cold until needed.