Place the bacon in a large, deep skillet. Cook over medium heat until the bacon is browned and crispy.

Remove the bacon from the pan, leaving the grease in the pan. Crumble the bacon and set it aside.

In the same pan, add the onion and garlic. Sauté until tender, about 3-5 minutes. Remove from the grease and discard the leftover grease.

Transfer the onion and garlic to a stock pot or Dutch oven. Add butter and melt it over medium heat.

When the butter is melted, add flour and whisk until smooth, forming a paste. The flour will start to brown slightly.

Gradually whisk in the milk and chicken broth. Keep whisking until the mixture thickens.

Add onion powder and parsley to the pot. Stir in the cubed potatoes and bring to a boil, stirring frequently.

Once boiling, cover the pot, reduce heat to low, and let simmer for 10 minutes. Stir occasionally to prevent burning at the bottom.

After simmering, mix in half the bacon crumbles, half the cheese, and all the sour cream. Stir until well combined, then taste. Add salt and pepper to season as you prefer.

Continue cooking, stirring frequently, until the cheese melts into the soup.

Serve topped with the remaining cheese, bacon crumbles, and sliced green onions for garnish.