Separate the onion into rings, then add to your melted butter.
I like to add a little kosher salt at this point. I keep my salt for cooking in a vintage glass refrigerator container.
Keep stirring your onions over medium heat. You will see that the salt is drawing moisture out of the onions. The onions won't begin to brown until all of that moisture has been boiled off. It helps to have a helper for this step, while you do other work in the kitchen.
|Now Onions Are Softened|
|Starting To Brown|