Spinach Cooked in Butter

This is my new favorite way to cook spinach.  It's very simple, but really good.
Finely dice one large clove of garlic.  Set a cast iron pan on medium heat and add a knob of butter.  Sautee the garlic until quietly fragrant, add a pinch of chili flakes, then a fistful of spinach.  Salt and pepper.  Toss the spinach to coat with butter, and cook until wilted.  Then add some more spinach--you'll be surprised how much spinach you can cook in this manner.  Continue to add salt & pepper in small amounts as you add more greens to the pan.  Taste for seasoning and serve.