2 lbs green beans, trimmed
2 tbsp unsalted butter
1 tsp grated lemon zest
Juice of 1/2 lemon
1 tbsp minced fresh rosemary leaves
Salt and pepper, to taste
Cook green beans in salted water about 5 minutes, or until tender but crisp. Remove from heat, drain and set aside.
Meanwhile, in small saucepan, over low heat, melt butter. Add lemon zest, juice rosemary, and salt and pepper to taste.
Toss together beans and butter mixture.