Cut, peel and slice the onions. Heat a big-ass pan or sauce pot. Drizzle some oil in it and dump the onions in.
Stir them for… um… ever. Juice will come out of the onions. When it evaporates, pour in a couple ounces of stock. Let it boil off.
Repeat this for what seems like too long. The onions will turn brownish. Keep going.
Use the stock sparingly. You will know that you are done when the onions are falling apart and sweet and mahogany brown. Season with the salt.
When it is dark brown and sweet and salty, you have succeeded.
Here’s the secret. Cook bratwursts on a grill. Shred or slice Gruyere cheese super thin.
Top brats with caramelized onions and Gruyere.
You now have French Onion Euro-dogs.