Sandwich spread. Especially roast beef.

I’m new to the world of crème fraiche. I stirred 2 T of buttermilk into 16 oz of fresh cream in a non reactive container, covered it, left it out at room temperature, and at the 24 hour mark, I had beautiful crème fraiche. I can use it to make a quick cheese sauce without a roux and it elevates mashed potatoes, but what else should I do with it? What are your favorite uses for it?