Crockpot Gruyère Cream Portobello Flank Steak Tips, FAQ & printable recipe

Tips for success

To get the most flavor out of the beef, consider searing the flank steak in a hot skillet for a couple of minutes per side before adding it to the slow cooker.

While this recipe is designed to be a dump-and-go, a quick sear adds a deep, caramelized crust that enhances the overall taste. If you do sear, be sure to deglaze the pan with a splash of broth or water and add those juices to the slow cooker for extra flavor.

If you prefer a thicker sauce, you can remove the beef and mushrooms from the slow cooker once they are done, then whisk a tablespoon of cornstarch with two tablespoons of cold water and stir it into the sauce. Cook on high for 10 to 15 minutes until the sauce thickens. Alternatively, you can let the sauce reduce on the stovetop in a saucepan. This is a great way to control the consistency to your liking.

Variations

• Add Bacon: For a smoky twist, cook 4 slices of bacon until crisp, crumble, and sprinkle over the finished dish. You can also replace the beef with bacon-wrapped pork tenderloin for a different flavor profile.
• Make it Spicy: Add a teaspoon of red pepper flakes or a diced jalapeño to the slow cooker along with the other ingredients. The heat will mellow as it cooks, leaving a subtle warmth that complements the creamy sauce.
• Use Chicken: Substitute boneless, skinless chicken thighs for the flank steak. Cook on low for 4 to 5 hours until the chicken is tender and reaches an internal temperature of 165°F (74°C). Shred the chicken and serve as a creamy stew.
• Vegetarian Version: Skip the beef and double the mushrooms, using a mix of portobello and cremini. Add a can of drained cannellini beans for protein. The cooking time will be shorter, about 3 to 4 hours on low, until the mushrooms are tender.

Storage and make-ahead

Fridge

Store leftover Gruyère cream portobello flank steak in an airtight container in the refrigerator for up to 4 days. Reheat gently before serving.

Freezer

Freeze in a freezer-safe container for up to 3 months. Thaw overnight in the refrigerator before reheating.

Reheat

Reheat in a saucepan over medium-low heat, stirring occasionally, until hot. Add a splash of broth or water if the sauce has thickened too much.

Leftovers can be stored in an airtight container in the refrigerator for up to 4 days. The flavors will continue to meld, making the leftovers even more delicious. To reheat, place the desired portion in a microwave-safe dish and heat in 30-second intervals, stirring in between, until hot.

Alternatively, reheat gently in a saucepan over medium-low heat, adding a splash of beef broth or water if the sauce has thickened too much. Do not let the dish sit out at room temperature for more than 2 hours.

This dish is ideal for making ahead. You can assemble the raw ingredients in the slow cooker insert and store it in the refrigerator overnight. In the morning, place the insert in the slow cooker base and start cooking.

Alternatively, you can cook the dish completely, let it cool, and store it in the refrigerator. When ready to serve, reheat gently on the stovetop or in the microwave. The flavors actually improve after a day in the fridge.

Serving ideas

Serve this slow cooker flank steak over creamy mashed potatoes, buttered egg noodles, or a bed of polenta to soak up the luxurious sauce. The toasted garlic brioche is perfect for dipping, but any crusty bread will work. For a complete meal, add a simple green salad with a tangy vinaigrette to cut through the richness, or steamed green beans for a pop of color and freshness.

For a more elegant presentation, transfer the beef and mushrooms to a serving platter and spoon the sauce over the top. Garnish with a sprinkle of fresh chopped parsley or thyme, if desired.

This dish is hearty enough to stand alone, but it also pairs well with roasted vegetables or a side of caramelized carrots. Leftovers make a fantastic sandwich filling on a crusty roll with a smear of horseradish cream.

Frequently asked questions

Recipe card

Crockpot Gruyère Cream Portobello Flank Steak

Prep 15 minCook 6 hTotal 6 h 15 minServes 6

Ingredients

• 2 lb flank steak, thinly sliced against the grain
• 8 oz portobello mushrooms, thickly sliced
• 6 shallots, peeled
• 8 oz cream cheese, softened
• 1 cup shredded Gruyère cheese
• toasted garlic brioche slices, for serving

Instructions

1. Place the sliced flank steak in the bottom of a 6-quart slow cooker. Scatter the portobello mushroom slices and peeled shallots over the beef. Drop the softened cream cheese in chunks on top, then sprinkle with the shredded Gruyère.
2. Cover the slow cooker with the lid. Cook on LOW for 6 to 8 hours, or on HIGH for 3 to 4 hours, until the beef is fork-tender and the sauce is bubbling. Let it rest for 3 minutes before slicing.
3. After the cooking time, check the beef by piercing a piece with a fork. It should shred easily and be very tender. If not, continue cooking for another 30 to 60 minutes. Let it rest for 3 minutes before slicing.
4. Turn off the slow cooker and let the beef rest in the sauce for at least 3 minutes before serving. This allows the juices to redistribute and the meat to become even more tender.
5. Using a slotted spoon, transfer the beef, mushrooms, and shallots to a serving platter or individual plates. Spoon the creamy sauce over the top. Serve immediately with toasted garlic brioche slices for dipping.

Contains: gluten, milk, eggs

Estimated nutrition per serving

Calories

520

Protein

38 g

Carbohydrates

10 g

Fat

36 g

Automatic estimate from the ingredient list, not laboratory-verified.