Heat 1 inch of vegetable or canola oil in a large frying pan over medium high heat.
Cut onions across into 1-inch rings and separate. Discard the outer layer of skin on your rings. Pour evaporated milk into a small, deep bowl. Mix flour with seasonings in a pie plate or shallow dish. Dip individual rings in milk, then coat in flour. And repeat for a double dip. Fry in a single layer in hot oil until golden brown. Remove to brown paper bag or paper towel lined surface to drain. Salt while hot, to your taste.
For dipping sauce, combine all ingredients in a bowl and stir.
Tip: refrigerate your onions and canned evaporated milk when you unpack from the grocery store. The colder the better for making onion rings!