Step 1

Preheat the oven to 350 degrees F.

Step 2

Place the potatoes on a roasting tray and bake for 45 minutes. When done, the tip of a paring knife should go through the potatoes easily.

Step 3

Slice the bacon into lardons (thin strips) and cook in a large, heavy-bottomed pot over medium heat until crisp. Remove the bacon from the pot with a slotted spoon and set aside, leaving the drippings in the pot.

Step 4

Add the flour to the drippings in the pot and stir to combine. Cook, without adding color, until the flour and fat has combined, about 1 minute. Pour in the milk while you whisk to incorporate. Cook over medium heat until bubbly and thickened, stirring frequently, about 15 minutes.

Step 5

Scoop out the potato pulp from the skins and add to the milk mixture. Mash with the back of a wooden spoon leaving it a little bit chunky.

Step 6

Add the cooked bacon (leaving a little out for garnishing the soup), 1 cup of the cheese, and season well with salt and pepper. Stir until the cheese has melted. Remove from the heat.

Step 7

Ladle the soup into bowls, drizzle with sour cream (from a squeeze bottle), sprinkle with remaining bacon bits, grated cheese and chives.