4 small leeks
2 Tbsp. unsalted butter
1/4 cup vegetable broth
2 Tbsp. fresh lemon juice
1 tsp. freshly grated lemon zest
1/2 tsp. salt
1/2 tsp. black pepper
Cut tops off leeks at the point where they turn dark green. Cut roots off. Cut leeks in half the long way and rinse well under running water, separating the segments, until all sand is removed. Cut lengthwise again to make quarters.
Melt butter in a big skillet over medium heat. Sauté leeks, stirring occasionally, for 5 minutes. Add remaining ingredients and cover pan. Cook without stirring for 10 minutes. Remove lid, increase heat to high, and cook 5 minutes until most of the liquid has evaporated.