• 3 tablespoons butter
• 4 leeks, sliced very thin
• 3 stalks celery, sliced very thin
• 2 medium potatoes, peeled and diced
• 3 cups (3/4 L) milk
• salt
• freshly ground pepper

Leeks tend to be gritty and need careful cleaning: cut off the roots and the coarse green tops, cut lengthwise through the remaining green tops starting within an inch of the white bottom, gently separate the stiff leaves, and rinse well under cold, running water.

Melt the butter in a large pot and add the leeks and celery. Cook for about 10 minutes over moderate heat, stirring often. Stir in 1 cup water, cover, and cook 10 minutes more. Add the potatoes and 2 more cups water, cover, and cook 10 minutes. Stir in the milk, cover, and cook until the potatoes are just tender, about 10 minutes more. Add salt and pepper to taste.

Lessons learned: all leeks have sand, there is no getting around it. Can be made with lactaid milk and margerine for a lactose-free meal. Consider using 2 cups water and 4 cups milk instead of 3 & 3. Don't forget to add the salt and pepper, or you'll be doing it for each bowl.