Cowboy Butter Broccoli Flank Steak: 5-Ingredient Crockpot Dinner Tips, FAQ & printable recipe

Tips for success

For the most tender beef, always slice flank steak against the grain—this shortens the muscle fibers and makes each bite easier to chew. If you have time, let the sliced steak sit at room temperature for 30 minutes before adding to the slow cooker, but never longer.

This helps it cook more evenly. Also, don't skip the rest time after cooking; it allows the juices to redistribute, keeping the meat moist.

The sauce is the heart of this dish. If you prefer a thicker gravy, mix 2 tablespoons of cornstarch with 2 tablespoons of cold water and stir into the sauce during the last 30 minutes of cooking.

For a thinner sauce, add a splash of beef broth. Taste before serving and adjust seasoning with salt and pepper—though the au jus mix is usually salty enough.

Variations

• Spicy Kick: Add 1-2 teaspoons of crushed red pepper flakes or a diced jalapeño along with the butter for a spicy twist. You can also stir in a few dashes of hot sauce before serving.
• Cheesy Finish: Stir in 1/2 cup of shredded cheddar or provolone cheese during the last 15 minutes of cooking, until melted and creamy. This adds a rich, cheesy layer to the sauce.
• Low-Carb Bowl: Skip the mashed potatoes and serve the beef and vegetables over cauliflower rice or zucchini noodles. The sauce is just as delicious without the starch.
• Swap the Vegetables: Use green beans, asparagus, or bell peppers instead of broccoli and mushrooms. Adjust the cook time so the vegetables are tender but not overcooked.

Storage and make-ahead

Fridge

Store leftovers in an airtight container in the refrigerator for up to 4 days. Reheat gently with a splash of broth or water to keep the sauce silky.

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 heated through. Add a splash of beef broth if the sauce has thickened too much.

Leftovers can be stored in an airtight container in the refrigerator for up to 4 days. Reheat gently in the microwave or on the stovetop with a splash of water or broth to loosen the sauce. The flavors continue to meld overnight, making leftovers even more delicious.

This dish is perfect for meal prep. Assemble the ingredients in the slow cooker insert the night before, cover, and refrigerate. In the morning, place the insert in the slow cooker and cook as directed. You can also cook the entire dish, let it cool, and store in the refrigerator for up to 4 days—just reheat before serving.

Serving ideas

This cowboy butter broccoli flank steak is a complete meal when served over creamy mashed potatoes, as shown. The potatoes soak up the rich, buttery sauce, making every bite satisfying.

For a lighter option, serve over steamed rice, quinoa, or cauliflower rice. A side of crusty bread is also wonderful for dipping into the sauce.

For a full spread, pair with a simple green salad dressed with lemon vinaigrette to cut through the richness.

The dish is hearty enough to stand alone, but it also welcomes additions like roasted carrots or a glass of full-bodied red wine. Garnish with fresh parsley or chives if you have them, though the video keeps it simple.

Frequently asked questions

Recipe card

Cowboy Butter Broccoli Flank Steak: 5-Ingredient Crockpot Dinner

Prep 10 minCook 6 hRest 5 minTotal 6 h 15 minServes 6

Ingredients

• 2 lb flank steak, thinly sliced against the grain
• 3 cups broccoli florets
• 8 oz baby bella mushrooms, sliced
• 1/2 cup garlic-herb cowboy butter (2 sticks), softened
• 1 oz au jus gravy mix
• creamy whipped mashed potatoes, for serving

Instructions

1. Place the thinly sliced flank steak strips in the bottom of a 6-quart slow cooker. Scatter the broccoli florets and sliced baby bella mushrooms evenly over the beef. Dot the top with the garlic-herb cowboy butter, then sprinkle the au jus gravy mix over everything. Do not stir.
2. 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 the broccoli is as soft as you like. The butter will melt into the au jus, creating a rich, golden sauce. Let it rest for 3 minutes before slicing.
3. Turn off the slow cooker and let the beef rest in the hot sauce for at least 3 minutes. This allows the juices to redistribute, keeping the meat moist and tender.
4. Using a serving spoon, lift a generous portion of the beef, broccoli, and mushrooms from the slow cooker, letting the sauce cling to each piece. Pile the mixture over a bed of creamy whipped mashed potatoes, then spoon extra au jus over the top.
5. Serve immediately while hot. The beef should be fork-tender, the broccoli tender but with a little bite, and the sauce rich and buttery. Add a sprinkle of fresh cracked pepper if desired (not shown).

Contains: gluten, milk

Estimated nutrition per serving

Calories

520

Protein

38 g

Carbohydrates

12 g

Fat

35 g

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