Velvety creamy potato soup loaded with bacon, cheddar, and chives is pure comfort in a bowl. This hearty, family-friendly vegetarian base soup warms you up on the coldest evenings.
Heat a large pot over medium heat and cook bacon until crisp. Transfer cooked bacon to paper towels and reserve 1 tablespoon of bacon fat in the pot.
Add unsalted butter to the bacon fat, then sauté chopped onion, carrot, and celery over medium heat until soft, about 6 minutes—be sure not to brown the vegetables.
Stir in flour and cook, stirring constantly, for 2 minutes to form a light roux. This thickens the soup without lumps.
Gradually whisk in chicken broth and add diced potatoes. Bring to a simmer, cover, and cook on low heat for 20 minutes until potatoes are very tender.
Remove about 1 cup of potato mixture and mash; return the mash to the pot. Stir in whole milk and 1 cup of shredded cheddar, simmering gently (do not boil) for 5 minutes.
Season with salt and pepper. Serve hot, garnished with remaining cheddar, crispy bacon, and chopped chives.