Name: Slow-Cooked Steak Diane Casserole
Prep time: 15 min
Cook time: 2 h
Total time: 5 min
Yield: 6
Ingredients: 2 lbs (900g) beef sirloin or chuck, cut into chunks; 2 tbsp olive oil; 1 large onion, finely chopped; 3 cloves garlic, minced; 2 cups mushrooms, sliced; 1/2 cup brandy or white wine (optional); 1 cup beef broth; 1 cup heavy cream; 2 tbsp Worcestershire sauce; 2 tbsp Dijon mustard; 1 tbsp tomato paste; Salt and pepper to taste; Fresh parsley for garnish; Tools You’ll Need:; Large oven-safe casserole dish; Frying pan or skillet; Wooden spoon

Slow-Cooked Steak Diane Casserole

There’s something special about a meal that fills the house with a mouthwatering aroma and brings everyone together around the table. This Slow-Cooked Steak Diane Casserole is one of those dishes that just screams comfort and coziness. The first time I made it was on a rainy Sunday, when my kids were bouncing off the walls, and I needed a recipe that felt indulgent but wouldn’t keep me stuck in the kitchen for hours.

The result? A luxurious, creamy mushroom sauce wrapping tender, slow-cooked steak like a warm, comforting hug. My family’s eyes lit up when they took that first bite, and even my pickiest eater couldn’t resist going back for seconds. The steak was melt-in-your-mouth perfect, and the sauce—oh, that sauce! Rich, savory, and full of flavor, it’s the kind of sauce that you’ll want to scoop up with every last bite of mashed potatoes.

It’s become a favorite for good reason: it’s simple to prepare, tastes like something you’d order at a fancy restaurant, and it delivers that sense of homely warmth we all crave. This casserole has now become a staple in my household, perfect for busy weeknights, family dinners, or even when you want to impress guests without too much fuss. If you’re looking for a recipe that delivers comfort, flavor, and joy, this one’s for you.

Questions I Often Get Asked About This Recipe:

Can I use a different cut of beef?
Yes! While I recommend tender cuts like sirloin or chuck for that fall-apart texture, you can also use stewing beef if that’s what you have on hand. Just ensure it’s cooked long enough to get tender.

Can I make this in a slow cooker instead of the oven?
Absolutely! You can cook this in a slow cooker on low for 6-8 hours or on high for 4-5 hours. The result will be just as delicious.

Can I freeze this casserole?
Yes, it freezes beautifully. Just let it cool completely, store it in an airtight container, and freeze for up to 3 months. Reheat it gently on the stove or in the oven until warmed through.

What can I serve this with?
Mashed potatoes are my go-to, but it’s also great with pasta, rice, or crusty bread to soak up all that creamy sauce.

Can I add vegetables to this dish?
Definitely! You can add peas, carrots, or even green beans during the last 30 minutes of cooking for a complete meal.

What You Need to Make Slow-Cooked Steak Diane Casserole:

Ingredients:

2 lbs (900g) beef sirloin or chuck, cut into chunks

2 tbsp olive oil

1 large onion, finely chopped

3 cloves garlic, minced

2 cups mushrooms, sliced

1/2 cup brandy or white wine (optional)

1 cup beef broth

1 cup heavy cream

2 tbsp Worcestershire sauce

2 tbsp Dijon mustard

1 tbsp tomato paste

Salt and pepper to taste

Fresh parsley for garnish

Tools You’ll Need:

Large oven-safe casserole dish

Frying pan or skillet

Wooden spoon

How to Make Slow-Cooked Steak Diane Casserole:

Preheat the oven to 325°F (160°C).

Sear the beef: In a frying pan, heat the olive oil over medium-high heat. Brown the beef chunks on all sides, working in batches to avoid overcrowding. Set the beef aside.

Cook the onions and mushrooms: In the same pan, add the chopped onions and cook until softened. Add the garlic and mushrooms, and cook until the mushrooms are golden.

Deglaze the pan: Pour in the brandy or wine (if using) to deglaze the pan, scraping up any browned bits. Let it simmer for 2-3 minutes.

Make the sauce: Add the beef broth, Worcestershire sauce, Dijon mustard, tomato paste, and heavy cream. Stir until well combined.

Combine and cook: Place the seared beef in your casserole dish and pour the sauce over it. Cover with a lid and bake in the preheated oven for 2 hours, until the beef is tender.

Serve: Garnish with fresh parsley and serve hot over mashed potatoes or your favorite side.

Tips:

Sear the beef well: Browning the beef adds depth and richness to the final dish.

Don’t skip the brandy: If you can, use the brandy for that classic Steak Diane flavor. The alcohol will cook off, leaving a subtle complexity.

Low and slow is key: Don’t rush the cooking process; slow-cooking ensures tender, flavorful meat.

Make ahead: This casserole tastes even better the next day, so feel free to prepare it in advance.

Fresh herbs: Garnish with parsley or even a sprinkle of thyme for a burst of freshness.

Latest Reviews:

⭐⭐⭐⭐⭐ “This dish was absolutely delicious! My whole family loved it, and there were no leftovers. Will definitely make again!” — Emily R.

⭐⭐⭐⭐ “Perfect for a cozy night in. The sauce was so creamy, and the beef was melt-in-your-mouth tender.” — Lisa M.

⭐⭐⭐⭐⭐ “Amazing recipe! I made it in my slow cooker, and it turned out perfect. Served it with mashed potatoes, and everyone asked for seconds.” — Megan T.

⭐⭐⭐ “Very good, but I think I’ll add more garlic and mushrooms next time. Otherwise, it was a hit!” — John K.

⭐⭐⭐⭐⭐ “This is now a go-to recipe in our house. So flavorful and easy to make.” — Sarah B.

Printable Recipe:

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