Use a blender or food processor to chop the cilantro, tomatillos, jalapeno together with the lime juice until finely chopped. Transfer to a small bowl.

In the same food processor, blend together the dressing mix, powdered garlic and mayonnaise and buttermilk. Whirl together.

Add about half the tomatillo and jalapeno mix and pulse two or three times.

Taste and adjust the consistency by adding more tomatillo. Salt and pepper to taste.

Add more mayo and buttermilk if desired.

Transfer to a container and refrigerate for at least a half an hour before serving.