Step by step

Method

4 steps

1. 1

   Peel and cube 4 large russet potatoes (about 2½ lb). Boil in salted water until a fork slides in with no hard center, 12–15 minutes. Drain well and leave them in the colander — excess water thins the soup.

2. 2

   In a heavy pot, melt 4 tablespoons butter over medium heat. Add 1 diced onion and cook until soft and translucent with a little golden edge, about 5 minutes. Sprinkle in 3 tablespoons flour and cook, stirring, 1 full minute so the raw flour taste cooks off — it should smell like toast, not paste.

3. 3

   Slowly whisk in 4 cups chicken or vegetable broth, then 1½ cups milk. Bring to a gentle simmer and cook 3–5 minutes until the soup lightly coats a spoon. Add the potatoes and mash some of them against the side of the pot for a chunky-creamy texture — leave plenty of soft cubes.

4. 4

   Stir in 1 cup shredded sharp cheddar and ½ cup sour cream off the boil until melted and smooth. Season with 1 teaspoon kosher salt and ½ teaspoon black pepper, tasting as you go. Ladle into bowls and top with crumbled bacon (from 6 cooked strips) and sliced green onions. You want thick, spoon-coating soup with soft potato chunks — not thin broth or a gluey flour paste.