01 -
Shred the cheddar cheese, measure sour cream and half and half, then allow them to reach room temperature.
02 -
Cook the ground beef in a large pot over medium-high heat, breaking it apart until fully browned. Drain excess fat and set beef aside.
03 -
Place peeled and chopped potatoes in a large saucepan, cover with cold water, add 0.5 teaspoon salt, and boil until fork-tender, about 10–15 minutes. Drain thoroughly. Mash potatoes with 1 tablespoon butter and sour cream until smooth and creamy. Reserve.
04 -
In the soup pot, melt 2 tablespoons butter over medium heat. Sauté diced onions until softened, about 5 minutes. Add minced garlic and cook an additional minute.
05 -
Stir in flour and cook for 1 minute, stirring constantly. Gradually pour in chicken broth while whisking to avoid lumps.
06 -
Mix in Worcestershire sauce, Italian seasoning, mustard powder, and ground sage. Slowly add half and half, stirring continuously. Bring to a gentle boil, then reduce to a simmer.
07 -
Add mashed potatoes to the broth. Stir until well blended. For extra creaminess, use an immersion blender or process in batches in a stand blender until smooth.
08 -
Return the browned ground beef to the pot along with frozen mixed vegetables. Cook over a gentle simmer until vegetables are heated through, about 5 minutes.
09 -
Gradually stir in shredded cheddar cheese until melted and soup is smooth.
10 -
Taste the soup and adjust with salt and freshly ground black pepper as needed. Serve hot.