1 tablespoon butter, melted
Juice and zest of 1 lemon
1/2 teaspoon salt
1/2 cup toasted walnuts
Fill a medium pot with 1 in. water, insert a steamer basket, and bring to a boil, covered. Put beans in steamer and cover. Steam until bright green and tender, 8 to 10 minutes. Drain. Put beans on a serving plate. Drizzle with butter and lemon juice. Sprinkle with zest, salt, and walnuts.