With only 15 minutes of prep, this easy slow cooker French Onion Osso Bucco dinner takes the flavors of French onion and turns it into a hearty dinner the whole family will love. Made with veal osso bucco, brown onions, carrots, celery, garlic, and tomato paste, it’s a delight for any evening.

To make French Onion Osso Bucco in your slow cooker or crockpot, start by searing the meat, then sauté onions and build the sauce with vegetables and herbs. Cook on low for 6 hours or high for 3 hours.

Every time I make this dish, the aroma fills the house and brings everyone to the table with anticipation.

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Can I Use Different Cuts of Meat for This Recipe?

Yes, you can use different cuts of meat if veal osso bucco isn’t available. Beef shanks are a great alternative, providing a similar texture and flavor. Just ensure the meat has some marbling for best results.

Slow Cooker French Onion Osso Bucco Ingredients

• 3 tbsp of olive oil (divided)
• 4 pieces of veal osso bucco (approximately 1.4 kg total), with excess fat trimmed
• 2 medium brown onions, cut into rings
• 1 large carrot, peeled and sliced
• 2 celery sticks, sliced
• 2 cloves of garlic, crushed
• 2 tbsp of tomato paste
• 1 tbsp of plain flour
• 1 tsp of beef stock powder
• 40g sachet of French onion soup mix
• 1 tsp of fresh thyme leaves, plus extra for garnishing
• Mashed potatoes, pasta, or rice for serving

How To Make Slow Cooker French Onion Osso Bucco

1. Prepare the cooking pan: Begin by heating 2 tsp of olive oil in a large frying pan over medium-high heat.
2. Brown the meat: Place the veal osso bucco in the hot oil and sear for about 2 minutes on each side until well browned, ensuring a rich flavor. Transfer the browned meat directly to the slow cooker.
3. Cook the onions: Reduce the frying pan’s heat to medium and add 1 tbsp of the remaining olive oil. Add the onion rings and sauté, stirring frequently, for about 7 minutes or until they become soft and take on a golden color.
4. Set aside onions: Once the onions are caramelized and golden, transfer them from the pan to a plate, setting them aside for later use.
5. Prepare the vegetable mixture: In the same pan, add the remaining olive oil, then toss in the sliced carrot and celery, cooking for about 3 minutes until they start to soften.
6. Make the sauce: Stir in the crushed garlic, cooking for 30 seconds before adding the tomato paste and plain flour. Gradually add 250 ml of water, stirring well to incorporate and lift any residues from the pan. Mix in the beef stock powder, French onion soup mix, and fresh thyme, bringing everything to a gentle simmer.
7. Combine and slow cook: Carefully pour the hot vegetable and sauce mixture over the seared meat in the slow cooker, then top with the cooked onions. Cover the slow cooker and set it to cook on low for 6 hours or high for 3 hours, until the meat is tender and flavorful.
8. Serve and enjoy: Serve the osso bucco sprinkled with extra thyme, accompanied by your choice of mashed potatoes, pasta, or rice.

Is It Necessary to Sear the Meat Before Slow Cooking?

It is highly recommended to sear the meat before placing it in the slow cooker. Searing the veal osso bucco caramelizes the surface, which enhances the dish’s depth of flavor and adds a rich color to the final presentation.

Recipe Tips

• Monitor Browning: When searing the veal, ensure it browns but does not burn; this will deepen the flavors without adding bitterness to your dish.
• Enhance Flavor with Wine: Before adding water to the sauce mixture, deglaze the pan with a splash of white wine to enhance the flavors and add an extra layer of complexity.
• Choose the Right Cookware: Use a heavy-based frying pan for even heat distribution when cooking the onions and vegetables, ensuring they cook evenly and do not stick.
• Modify the Thyme: While fresh thyme is recommended, you can also use dried thyme; use one-third of the amount because it’s more concentrated in flavor.

Recipe Variations

• Alternative Meats: If veal is not available, you can substitute it with beef shanks; adjust cooking times accordingly, as beef might cook quicker depending on the cut.
• Add More Vegetables: Include chunks of parsnip or sweet potato with the carrots and celery for additional sweetness and texture in the dish.
• Spicy Kick: Add a teaspoon of crushed red pepper flakes to the sauce mixture if you enjoy a bit of heat, which complements the sweetness of the onions nicely.
• Herb Variations: Try incorporating rosemary or sage instead of thyme for a different herbal note that still pairs wonderfully with the rich flavors of the dish.

What To Serve With French Onion Osso Bucco

Serve your French Onion Osso Bucco with hearty, rustic sides like garlic mashed potatoes, Fresh Green Beans, roasted parsnips, buttered egg noodles, and saffron-infused rice.

You can also pair it with baked polenta cakes or a crisp fennel salad for a lighter touch.

How To Store Leftover French Onion Osso Bucco

In The Fridge:

Store leftover French Onion Osso Bucco in an airtight container in the fridge. I prefer to let it cool to room temperature before storing it to maintain the best quality. Consume within 3 to 4 days for the best taste and safety.

In The Freezer:

Unfortunately, French Onion Osso Bucco doesn’t freeze well due to the texture of the veal. Freezing might make the meat grainy and less enjoyable. I’d suggest enjoying it fresh or stored in the fridge.

How To Reheat Leftover French Onion Osso Bucco

Reheat your leftover French Onion Osso Bucco gently in a covered saucepan over medium heat until it’s thoroughly warm. Stir occasionally to ensure even heating. If I were you, I’d add a splash of broth to keep it moist during reheating.

Check out More Slow Cooker Recipes:

• Slow Cooker Chicken and Leek Casserole
• Slow Cooker Liver And Bacon Casserole
• Slow Cooker Pheasant Red Wine Casserole