Shred the cheese from a block, measure out the sour cream and half and half. Let them sit out at room temperature.

Cook and crumble the ground beef over medium-high heat until cooked through. Drain grease and set aside.

Peel the potatoes and cut them into thirds. Add to a stock pot, cover with 1 inch of water, add salt and boil gently for 10-15 minutes until fork tender. Drain and gently mash, adding sour cream and 1 tablespoon of butter. Set aside.

Melt 2 Tablespoons of butter over medium heat. Add onions and cook until softened, about 5 minutes. Add garlic and cook for 1 more minute.

Whisk in flour and stir as it cooks for 1 minute.

Add chicken broth in splashes, stirring continuously and loosening any beef remnants from the bottom of the pot.

Add Worcestershire sauce, Italian seasoning, mustard powder, and sage. Slowly add half and half, bring to a boil, then reduce to a simmer.

Stir in the potatoes until well-combined into the broth. Blend until creamy if desired.

Add ground beef and frozen vegetables, heat through for 5 minutes.

Remove from heat and gradually stir in shredded cheese until combined. Season with salt/pepper if desired and serve.