Healthy Avocado Salad Dressing

I love that this recipe means that my salad dressing counts as a serving of vegetables.  How often is salad dressing THIS guilt free? Great  for when avocadoes are in abundance.  Would be good on tacos as well.

Ingredients:
1 ripe avocado, peeled and cored
3/4 cup water
2 tbsp sour cream or yogurt
1 tsp lime zest
3-4 tbsp lime juice (fresh)
1/2 tsp cumin
1/4-1/2 tsp chili powder
1/2 tsp salt
1/2 tsp pepper
cayenne for the spicy lovers
2 green onions, chopped
1 clove garlic

Directions:
chop up avocado and add to blender
add rest of ingredients
blend till smooth
taste, readjust seasoning and water