Heat the olive oil in a large pot over medium heat. Add the diced onion and minced garlic, cooking until softened and fragrant, about 3-4 minutes.

Add the ground beef to the pot, breaking it up as it cooks. Continue cooking until the beef is browned and fully cooked through, then drain any excess grease.

Stir in the diced potatoes and chicken broth. Bring the mixture to a boil, then reduce the heat to low and let it simmer for 15-20 minutes, or until the potatoes are tender.

Pour in the milk and heavy cream, stirring to combine. Allow the soup to heat through, but avoid letting it boil.

Gradually add the shredded cheddar cheese to the pot, stirring constantly until the cheese is fully melted and the soup is smooth.

Season the soup with salt and pepper to taste. Let the soup simmer for an additional 5-10 minutes to allow the flavors to meld and the soup to thicken slightly.

Ladle the soup into bowls and serve hot. For extra flavor, garnish with more shredded cheese, crispy bacon bits, or sliced green onions if desired.