Cozy Ground Beef Casserole My Familys Cottage Pie Secret

Instructions:

1. Heat olive oil in a large skillet over medium heat. Add onion, carrots, and celery and sauté until softened, about 8-10 minutes.
2. Add ground beef and cook, breaking it up with a spoon, until browned. Drain off any excess grease.
3. Stir in thyme, rosemary, and smoked paprika. Cook for 1 minute more.
4. Sprinkle flour over the beef mixture and cook for 1 minute, stirring constantly.
5. Gradually whisk in beef broth, scraping up any browned bits from the bottom of the pan.
6. Stir in crushed tomatoes, Worcestershire sauce, and tomato paste. Bring to a simmer.
7. Reduce heat to low, cover, and simmer for 20 minutes, stirring occasionally, until the sauce has thickened. Season with salt and pepper to taste.
8. Place potatoes in a large pot and cover with cold water. Bring to a boil and cook until tender, about 15-20 minutes.
9. Drain potatoes well and return them to the pot.
10. Mash potatoes with a potato ricer or masher until smooth.
11. Gradually add warm milk and butter, beating until light and fluffy.
12. Stir in sour cream and season with salt and white pepper to taste.
13. Preheat oven to 375°F (190°C).
14. Pour the beef filling into the prepared baking dish.
15. Spread the mashed potato topping evenly over the beef filling.
16. Sprinkle with shredded cheddar cheese (if using).
17. Bake for 20-25 minutes, or until the topping is golden brown and the filling is bubbly.
18. Let stand for 10 minutes before serving.