Preheat the oven to 400 degrees F. Mix all the ingredients for the onion dip in a large bowl. Then scoop into a round baking dish and smooth the dip evenly in the dish. Place in the oven for 20 minutes.
Meanwhile heat the oil in a large sauce pot, to 375 degrees F. Slice the onions into thin strips and place in the buttermilk to soak. In a shallow dish, mix the flour, salt and pepper. Once the oil is hot, drain the onions and toss in the flour mixture to coat. Shake of the excess four and carefully dunk all the onions into the hot oil.
Fry the onions for 1-2 minutes, until golden brown, then scoop out with a skimmer and place them on a paper-towel lined plate. Sprinkle with additional salt.
Remove the hot onion dip from the oven and sprinkle the french fried onions over the top. Place back in the oven for 5 more minutes until bubbly and cooked through.
Serve warm with veggies, chips, pita chips, crackers, or bread.