Slow cooked Steak Diane casserole with tender beef, creamy mushroom sauce, brandy, garlic, and herbs. Easy oven-baked beef recipe perfect for family dinners, meal prep, or Sunday lunch. Served with mashed potatoes and vegetables. Rich, comforting dish ideal for colder days or batch cooking.

This rich and comforting Steak Diane Casserole combines tender chunks of slow-cooked beef with mushrooms, brandy, and a creamy, flavorful sauce. Cooked low and slow in the oven, it’s the perfect meal for a cozy weekend or a make-ahead dinner.

Ingredients

2 tbsp vegetable oil
1.5 kg (3.3 lb) braising beef or casserole beef, cut into bite-sized chunks
3 tbsp plain (all-purpose) flour (use gluten-free if needed)
½ tsp salt
½ tsp freshly ground black pepper
1 large onion, peeled and chopped
4 garlic cloves, peeled and minced
2 tbsp tomato purée
4 tbsp brandy or whisky
1 tbsp Worcestershire sauce
1 litre (4¼ cups) beef stock (homemade, cubes, or bouillon)
300 g (10.5 oz) chestnut mushrooms, thickly sliced
1 tbsp cornflour (cornstarch) mixed with 3 tbsp cold water (optional, for thickening)
120 ml (½ cup) double (heavy) cream
Small bunch of fresh parsley, roughly chopped
Pinch of black pepper

Instructions

Preheat the oven to 160°C (320°F fan).
Brown the beef:
In a large bowl, toss the beef with the flour, salt, and pepper until evenly coated. Heat the oil in a large oven-safe casserole pan over high heat. Add the beef and cook for 6–8 minutes, turning until browned all over.
Add the aromatics:
Reduce heat to medium. Add the chopped onion and cook for 3–4 minutes, stirring regularly, until softened. Stir in the garlic and tomato purée and cook for 1 minute.
Deglaze and build the base:
Pour in the brandy or whisky and Worcestershire sauce. Add the stock and sliced mushrooms. Stir well, scraping up any browned bits from the bottom of the pan.
Slow cook in the oven:
Bring everything to a gentle boil, then cover with a lid and transfer the pan to the oven. Cook for 3 hours, until the beef is tender. Stir once or twice in the final hour to ensure it doesn’t dry out. Add a splash of hot water or stock if needed.
Finish the sauce:
If the sauce needs thickening, stir in the cornflour slurry and simmer gently on the stovetop until thickened. Then stir in the cream, and finish with chopped parsley and a pinch of black pepper.
Serve hot with mashed potatoes and green vegetables like broccoli, green beans, or kale.

Tips

Use a heavy-based casserole dish with a tight-fitting lid to retain moisture.
Sear in batches if your pan is small—this helps avoid steaming the meat.
For richer flavor, use beef stock made with bone broth or homemade bouillon.
Deglaze properly: Stir well after adding brandy to lift up the flavorful bits stuck to the pan.

Variations and Substitutions

Alcohol-free: Skip the brandy/whisky and add an extra splash of stock or a teaspoon of balsamic vinegar for depth.
No cream? Use crème fraîche or a little Greek yogurt stirred in at the end (off heat) for a lighter finish.
Mushroom options: Chestnut mushrooms work best, but button or portobello mushrooms can be used.
Make it gluten-free: Use gluten-free flour and ensure the stock and Worcestershire sauce are gluten-free.

FAQs

Can I make this in a slow cooker?
Yes, brown the beef and onions first, then transfer everything to a slow cooker. Cook on low for 7–8 hours or on high for 4–5 hours.

How long will it keep?
Store leftovers in the fridge for up to 3 days or freeze for up to 3 months. Reheat gently on the stovetop or in the oven.

Can I use a different cut of beef?
Yes. Any slow-cooking cut such as chuck, shin, or brisket will work well.

Serving Suggestions

Classic mashed potatoes are ideal for soaking up the sauce.
Serve with steamed greens, such as kale, green beans, or tenderstem broccoli.
Add crusty bread or buttery baby potatoes for a more rustic meal.
For a lighter pairing, serve with cauliflower mash or buttered cabbage.

Why You’ll Love This Recipe

Deep, rich flavor from slow-cooked beef and brandy-infused sauce
Tender and comforting—perfect for colder months or special meals
Versatile and freezer-friendly, making it ideal for batch cooking
Restaurant-style dish you can easily make at home