Cowboy Butter Portobello Beef Bites Slow Cooker Recipe Tips, FAQ & printable recipe

Tips for success

For the best flavor, sear the beef cubes in a hot skillet before adding them to the slow cooker. This adds a deep, caramelized crust that enhances the overall richness of the dish.

If you're short on time, you can skip this step—the slow cooker will still produce a delicious meal, but searing takes it to the next level.

To make your own garlic-herb butter, combine 1/2 cup (1 stick) of softened unsalted butter with 2 cloves of minced garlic, 1 tablespoon of chopped fresh parsley, 1 teaspoon of fresh thyme leaves, and a pinch of salt.

Mix until well combined. You can also add a teaspoon of Dijon mustard for extra tang. Store any leftover butter in the refrigerator for up to a week.

Variations

• Add Bacon: For a smoky twist, cook 4 slices of bacon until crisp, crumble, and stir into the finished dish just before serving. The bacon adds a salty, smoky flavor that pairs beautifully with the garlic-herb butter and beef.
• Spicy Kick: Add 1-2 teaspoons of red pepper flakes or a chopped jalapeño along with the au jus mix for a subtle heat. The spice will infuse the sauce as it cooks, giving the dish a gentle warmth without overwhelming the other flavors.
• Herb Swap: If you don't have garlic-herb butter, use a combination of 1/2 cup unsalted butter, 2 minced garlic cloves, and 1 teaspoon each of dried rosemary, thyme, and oregano. This creates a similar flavor profile with dried herbs that are often on hand.
• Vegetable Boost: Add 2 large carrots, peeled and cut into 1-inch chunks, and 2 celery stalks, sliced, along with the mushrooms and shallots. The vegetables will soften and absorb the sauce, adding extra heartiness and nutrition to the dish.

Storage and make-ahead

Fridge

Store leftovers in an airtight container in the refrigerator for up to 4 days. Reheat gently on the stovetop or microwave, adding a splash of broth if needed.

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 warmed through. Add a splash of beef broth or water if the sauce is too thick.

Store any leftover beef and sauce in an airtight container in the refrigerator for up to 4 days. The flavors will continue to meld, making the leftovers even more delicious. Reheat gently on the stovetop or in the microwave, adding a splash of water or beef broth if the sauce has thickened too much.

This recipe is perfect for meal prep. You can assemble all the ingredients in the slow cooker insert the night before, cover, and refrigerate.

In the morning, place the insert in the slow cooker base and cook as directed. You may need to add 30 minutes to the cooking time if starting from cold. Alternatively, cook the full recipe and freeze portions for later.

Serving ideas

Serve the beef bites over a generous scoop of creamy whipped mashed potatoes, spooning the garlic-herb butter au jus over the top.

The potatoes soak up the rich sauce, balancing the savory beef and earthy mushrooms. For a lighter option, serve over rice, polenta, or even crusty bread to mop up every drop.

This dish pairs well with a simple green vegetable, such as steamed green beans or sautéed spinach. A crisp salad with a lemony vinaigrette can cut through the richness. For a complete meal, add a glass of full-bodied red wine, like a Cabernet Sauvignon or Zinfandel, to complement the beef and herbs.

Frequently asked questions

Recipe card

Cowboy Butter Portobello Beef Bites Slow Cooker Recipe

Prep 10 minCook 6 hTotal 6 h 10 minServes 6

Ingredients

• 2 lb beef chuck stew meat, cut into 1-inch cubes
• 8 oz portobello mushrooms, thickly sliced
• 6 shallots, peeled and halved
• 1/2 cup garlic-herb butter (2 sticks), softened
• 1 oz dry au jus mix
• creamy whipped mashed potatoes, for serving

Instructions

1. Place the cubed beef chuck in the bottom of a 6-quart slow cooker in an even layer. Season lightly with salt and pepper if desired, though the au jus mix will add seasoning. Spread the beef out so it covers the bottom of the insert evenly.
2. Layer the thickly sliced portobello mushrooms and peeled halved shallots over the beef. No need to stir—the layers will meld as they cook. The mushrooms will release moisture, helping to create a rich sauce.
3. Place the garlic-herb butter pieces over the top of the beef and vegetables. Sprinkle the dry au jus mix evenly over everything. Do not add any liquid—the beef and mushrooms will release enough moisture during cooking.
4. Cover the slow cooker and cook on LOW for 6 to 8 hours, or on HIGH for 3 to 4 hours, until the beef is fork-tender and easily shreds. The internal temperature of the beef should reach at least 145°F (63°C) for safety, but for maximum tenderness, cook until it exceeds that and the meat is falling apart. Let it rest for 3 minutes before slicing.
5. After the cooking time, use a fork to test the beef. It should shred easily with no resistance. If it's still tough, continue cooking for another 30 to 60 minutes. Once done, let the beef rest in the sauce for at least 3 minutes before serving.
6. Spoon the creamy whipped mashed potatoes onto serving plates. Ladle the beef, mushrooms, shallots, and plenty of the garlic-herb butter au jus over the top. Serve hot, with extra sauce spooned over each portion.

Contains: milk, gluten

Estimated nutrition per serving

Calories

580

Protein

36 g

Carbohydrates

18 g

Fat

38 g

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