In a Dutch oven over medium-high heat, add 1 pound of lean ground beef or lamb. Cook for 8–10 minutes, breaking it apart with a spoon until it's well-browned and crumbles easily. Drain any excess fat before moving on to the next step.

Add 2 tablespoons of butter to the pot and allow it to melt. Stir in 1 chopped medium onion, sautéing for about 5 minutes until it becomes translucent and fragrant. Next, add 4 minced garlic cloves, 1/2 teaspoon of Italian seasoning, and 2 tablespoons of tomato paste. Cook for an additional minute.

Return the browned meat to the pot, then pour in 4 cups of chicken or beef broth. Stir in 1/2 tablespoon of Worcestershire sauce and 2 diced medium-to-large Russet potatoes. Bring the mixture to a boil, then reduce the heat to simmer. Cover the pot slightly and let it cook for about 20 minutes, or until the potatoes are fork-tender.

With the soup simmering, gently mash some of the potatoes in the pot to create a thicker texture. In a small bowl, mix 1/2 tablespoon of cornstarch with a bit of water to form a slurry, then stir this into the soup. Next, add 2 cups of frozen mixed vegetables and continue simmering until they are heated through and tender—about 5 minutes.

Remove the pot from heat and stir in 1 cup of heavy whipping cream, mixing until well combined. Heat the soup gently without boiling to avoid curdling the cream. Finally, taste and adjust the seasoning with salt and pepper as needed.