Blend butter, chile, vinegar, and salt in mini processor until smooth.
Transfer to small bowl, do ahead can be made 3 days ahead.
Cover and chill.
Cook beans in large pot of boiling salted water until crisp tender, about 5 minutes; drain and pat dry.
Do ahead can be made 3 hours ahead.
Let stand at room temperature.
Melt chipotle butter in large pot over medium high heat.
Add beans and toss until coated and heated through, about 3 minutes.
Transfer to bowl.
Chipotle chiles are dried, smoked jalapenos canned in a spicy tomato sauce, which is sometimes called adobo.
They are available at some supermarkets, specialty foods stores, and Latin markets.