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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