Brown the Ground Beef: In a large Dutch oven, cook the ground beef over medium heat, breaking it up with a spatula. Season with oregano, thyme, salt, and pepper. Cook until browned and cooked through. Remove from the pot and set aside.
Cook Vegetables: In the same pot, melt the butter and sauté the onion, carrot, and celery for about 10 minutes, until softened. Add the garlic, oregano, and thyme and cook for another minute.
Make the Roux: Stir in the flour and cook for 1 minute, until it thickens slightly.
Deglaze the Pot: Add a splash of chicken broth to deglaze the pot, scraping any browned bits off the bottom.
Simmer the Soup: Add the remaining chicken broth and elbow macaroni. Bring the soup to a simmer and cook for 5-7 minutes, or until the pasta is al dente.
Add Cream and Cheese: Stir in the heavy cream and shredded cheddar cheese, and continue stirring until the cheese is melted and smooth.
Add Ground Beef: Return the cooked ground beef to the pot and stir everything together. Taste and adjust seasoning with salt and pepper as needed.
Optional: Add a splash of white balsamic vinegar for a subtle tangy flavor.
Serve: Serve the soup topped with burger bun croutons, chopped green onions, and extra shredded cheddar for added flavor and crunch.