Begin by heating the olive oil in a large pot or Dutch oven over medium heat. Once the oil is hot, add the chopped onion and minced garlic. Sauté them together until the onion becomes soft and translucent, which should take about 3-4 minutes. Stir frequently to prevent burning.
Next, add the ground beef into the pot, using a spatula to break it into smaller pieces. Cook until the beef is browned and fully cooked through, approximately 6-8 minutes. If there is excess fat in the pot after cooking, consider draining it for a lighter soup.
Once the beef is cooked, incorporate the diced potatoes into the pot along with the beef broth, Worcestershire sauce, and Dijon mustard. Stir well and bring the mixture to a rolling boil. Reduce the heat to low after boiling and allow it to simmer for 15-20 minutes, or until the potatoes are tender and easily pierced with a fork.
After the potatoes are tender, pour in the milk, and add the shredded cheddar cheese and sour cream. Stir the soup continuously for about 5 minutes, or until the cheese has melted fully and the soup achieves a creamy consistency.
Taste the soup, then season it with salt and black pepper according to your preference. Adjust the seasoning to enhance the flavors.
Once seasoned, remove the pot from heat. Carefully ladle the soup into individual bowls, making sure to scoop up a good mix of meat, potatoes, and broth in each serving. Top with fresh chopped parsley for a burst of color and freshness before serving.
Notes
For an inviting presentation, serve the soup with crusty bread on the side for dipping. Sprinkle a little extra cheddar cheese on top of each bowl and perhaps a dollop of sour cream for extra flavor!