Heat large pot over medium heat.
Add olive oil and butter to the pot.
Add all of the sliced onions to the pot and season with salt.
Cook for approx 30 minutes, stirring every so often, to brown the onions.
Once the onions are brown, add white wine to deglaze the pan (scrape up the brown bits from the bottom of the pan).
Add 1/4 tsp of konjac flour or xanthum gum to onions and stir.
Add beef broth and herbs to the pot and simmer for 20 minutes.
Once the soup is done cooking, remove the bouquet garni (herbs). Divide the soup into bowls and enjoy!