Suggestions for cooking turnip greens?

I bought a large bag of turnip greens for the first time at a farmer's market. I've had some with salad dressing and some in sandwiches, but I'd like to cook and eat the rest while they're still good (purchased 5 days ago).

I tried out an online recipe that sauteed them in bacon grease. It was delicious but, as you might expect, very calorific. I still have about 4 cups of greens left - does anyone have healthy recipe ideas? Thanks!