In a large bowl, mix mayo, sour cream, and buttermilk.
Blend until smooth for a creamy base.
Add parsley, dill, salt, sugar, cumin, garlic, pepper, paprika.
Whisk until evenly mixed.
Stir in onion, hot sauce, cayenne, and chilli powder.
Ensure the mixture is uniform.
Refrigerate for 30 minutes for the flavours to meld.
Now your Southwest Ranch Sauce is ready!
Use as creamy sauce for wings or dip with veggies.