Pretzel Soup with Peanut Roux

• 8 to 10 3-inch (7.5-cm) unsalted pretzels (8 ounces/

Break the pretzels into small pieces and put them in a deep bowl. Cover with 3 cups (750 ml) of the cider and soak 1 to 2 hours. Transfer to a saucepan and add another 4 cups (1 liter) of cider, the butter, and the salt. Cover and cook over low heat until reduced to mush. Purée in a food processor until smooth, then pour the batter into a clean saucepan and thin to a vichyssoise consistency wit