1. Spread the chopped walnuts on a baking sheet. Bake at 300° F. for 10 minutes.
2. Cut the beans in half and sprinkle with salt. Steam them for 8 to 10 minutes. Plunge into cold water; drain.
3. Melt the butter in a large skillet on medium heat. Add the green onion, rosemary and lemon juice with the beans. Cook for 3 minutes, stirring constantly. Sprinkle with 1 tablespoon grated lemon rind.