5 Ingredient French Onion Soup (paleo)

The local onions have been very nice at the co-op lately - most notably that they are very LARGE! One of my staples of late is French Onion soup. I posted a GF version about two years ago (my first FO soup ever) and I have since simplified things down to this very basic, but delicious recipe.  I do think that part of why this soup tastes so good is due to the venison Bone Broth. I have not done a post about bone broth, but fellow Minneapolitan blogger at Sustainable Paleo has, and really, bone broth tastes about 10 times better than anything you can buy (and is really good for you and your bod). So, I cannot vouch for this soup if you are having it with store bought broth, but with bone broth, it is super good and very easy and you don't need any other herbs/spicing.

5 Ingredient French Onion Soup (serves 4)
4 T. butter or ghee
3 large onions
2-3 pints Venison/Beef Bone Broth
3/4 c. dry wine (either white or red seems to work fine - but dryer is better)
celtic sea salt (in my experience this salt makes soup more flavorful than any other)

1. Slice onions as thinly as you feel motivated to go for - the thinner the better to carmelize and be silky in your soup.
2. In a heavy pot, turn heat on medium heat and melt the butter. Add onions. Stir every so often and keep your eye on the onions. This is the carmelizing stage, and it takes a bit of time. You want the onions to turn nice and brown, so keep plodding along until they get there.
3. Pour in wine and stir/scrape the bottom of the pan to deglaze any buttery-onion bits that might have stuck there. Add broth (2 pints will be a thicker soup, 3 will be more broth-y! Both are good). Bring to a boil and let simmer for a few-10 minutes.
4. Salt to taste - it generally takes more than I think - a Tablespoon or two. Serve!
(Sometimes, depending on the wine, I do want a little acid in there, in which case it becomes 6 ingredients and I add a splash of cider vinegar...)