Place beef pieces in a large Dutch oven or soup pot over medium heat. Cook until the beef is crisp and browned.

Remove the cooked beef pieces with a slotted spoon and set them aside. Leave the rendered beef fat in the pot.

Add the butter and chopped onion to the pot. Cook over medium heat until the onions are tender, about 3-5 minutes.

Stir in the minced garlic and cook until fragrant, which takes about 30 seconds.

Sprinkle the all-purpose flour over the ingredients in the pot. Stir until smooth, using a whisk if needed, to create a roux.

Add the diced potatoes to the pot along with the chicken broth, milk, heavy cream, salt, pepper, and ancho chili powder. Stir all the ingredients well to combine.

Bring the mixture to a boil, then reduce the heat and cook until the potatoes are tender when pierced with a fork, approximately 10 minutes.

Reduce the heat to a simmer. Carefully remove approximately half of the soup (about 5 cups) to a blender and puree until smooth. Alternatively, use an immersion blender directly in the pot.

Return the pureed soup to the pot. Stir in the sour cream and the reserved crispy beef pieces. Mix everything well.

Allow the soup to simmer for 15 minutes before serving.

Top your hearty potato soup with additional sour cream, beef, shredded cheddar cheese, or fresh chives. Enjoy every warm spoonful!