Crème de concombres

• 3 tablespoons (45 g) butter
• 1 large onion, peeled and sliced

Melt the butter in a 5 to 6-quart (5–6 L) pot, mix in the onion and sauté over medium-low heat, stirring occasionally; for 6 to 8 minutes. Add the potatoes, pour on the chicken broth or water, and season l