Dinner · Part 3 of 3: Tips & recipe card

Cowboy Butter Flank Steak Crockpot Dinner: Set-and-Forget Tips, FAQ & printable recipe

Name: Cowboy Butter Flank Steak Crockpot Dinner: Set-and-Forget
Prep time: 10 min
Cook time: 8 h
Total time: 8 h 15 min
Cuisine: American
Ingredients: 2 lb flank steak, thinly sliced against the grain; 1 lb baby carrots; 1 1/2 lb red bliss potatoes, quartered; 2 sticks garlic-herb cowboy butter (store-bought or homemade); 1 oz au jus gravy mix; creamy whipped mashed potatoes (for serving)

By Clara Weller · Oct 28, 2026

Slow cooker filled with tender flank steak, baby carrots, and red potatoes in a golden butter au jus.

Prep: 10 min
Cook: 8 h
Total: 8 h 15 min
Serves: 6

Includes 5 min resting

Tips for success

For the best flavor, sear the flank steak strips in a hot skillet with a little oil before adding them to the slow cooker. This adds a deep, caramelized crust that enhances the overall taste. If you're short on time, you can skip this step, but it's worth the extra few minutes.

To make the gravy thicker, remove the beef and vegetables from the slow cooker and whisk in a slurry of 1 tablespoon cornstarch and 2 tablespoons cold water.

Simmer the liquid on the stovetop for a few minutes until it thickens. This is a great way to ensure every bite is coated in rich, velvety sauce.

Variations

Spicy Kick: Add 1-2 sliced jalapeños or a teaspoon of red pepper flakes along with the other ingredients for a subtle heat that complements the rich butter.
Mushroom Medley: Add 8 oz of sliced cremini mushrooms to the slow cooker with the other vegetables. They will absorb the savory flavors and add an earthy depth.
Herb Swap: If you don't have garlic-herb cowboy butter, use regular butter and add 2 teaspoons of dried Italian seasoning and 2 cloves of minced garlic to the pot.
Vegetable Boost: Add 2 cups of chopped celery and 1 large onion, sliced, to the slow cooker for extra flavor and texture. This stretches the dish to serve more people.

Storage and make-ahead

Fridge: Store leftovers in an airtight container in the refrigerator for up to 4 days. The gravy will thicken as it cools; add a splash of broth when reheating.
Freezer: This dish freezes well for up to 3 months. Cool completely, then transfer to freezer-safe containers. Thaw overnight in the refrigerator before reheating.
Reheat: Reheat gently on the stovetop over medium-low heat, or in the microwave in 30-second intervals. Add a little beef broth or water to loosen the gravy if needed.

Store any leftovers in an airtight container in the refrigerator for up to 4 days. The flavors will continue to meld and develop, making the leftovers even more delicious.

Reheat gently in the microwave or on the stovetop, adding a splash of beef broth if the gravy 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, simply place the insert in the slow cooker and cook as directed. You can also cook the entire dish ahead of time and reheat it when ready to serve.

Serving ideas

Serve this cowboy butter flank steak over a bed of creamy mashed potatoes to soak up every bit of the rich gravy.

The smooth, buttery potatoes are the perfect counterpoint to the tender beef and hearty vegetables. For a complete meal, add a simple green salad or steamed green beans on the side.

This dish also pairs well with crusty bread or buttered noodles to catch the extra sauce. If you have leftovers, they can be turned into a delicious beef pot pie or served over rice for a quick lunch. The possibilities are endless, and every serving is just as comforting as the last.

Frequently asked questions

Can this recipe be made with chicken instead of beef?

Yes, but the cooking time will need to be adjusted. Chicken thighs would work well and should be cooked until they reach 165°F (74°C). Reduce the cooking time to about 4-5 hours on low. The flavors will still be delicious, though the beefy au jus will pair differently.

How can the gravy be thickened?

After cooking, remove the beef and vegetables from the slow cooker. Whisk 1 tablespoon of cornstarch with 2 tablespoons of cold water to make a slurry, then stir it into the hot liquid. Cook on high for 10-15 minutes until the gravy thickens. Return the beef and vegetables to the pot.

What is the best cut of beef for this recipe?

Flank steak is ideal because it becomes tender when slow-cooked. Other good options include sirloin, round steak, or even chuck roast, which has more marbling and will become very tender. Just be sure to slice against the grain.

Can this dish be cooked on high instead of low?

Yes, you can cook it on high for about 4 hours instead of 8 hours on low. However, the beef may be slightly less tender than when cooked low and slow. Always check the internal temperature reaches 145°F (63°C).

Is it necessary to brown the beef before adding it to the slow cooker?

Browning is optional but recommended. It adds a richer flavor through the Maillard reaction. If you're short on time, you can skip it, but the dish will have a slightly less complex flavor.

Recipe card

Cowboy Butter Flank Steak Crockpot Dinner: Set-and-Forget

Prep 10 minCook 8 hRest 5 minTotal 8 h 15 minServes 6

Ingredients

2 lb flank steak, thinly sliced against the grain
1 lb baby carrots
1 1/2 lb red bliss potatoes, quartered
2 sticks garlic-herb cowboy butter (store-bought or homemade)
1 oz au jus gravy mix
creamy whipped mashed potatoes (for serving)

Instructions

Place the thinly sliced flank steak strips in the bottom of a 7-quart slow cooker. Scatter the baby carrots and quartered red bliss potatoes over the beef. Place the two sticks of garlic-herb cowboy butter on top, then sprinkle the au jus mix evenly over everything.
Cover the slow cooker with the lid. Cook on LOW for 8 hours, or on HIGH for 4 hours, until the beef is fork-tender and the potatoes are easily pierced with a knife. Let it rest for 3 minutes before slicing.
After the cooking time, use an instant-read thermometer to check the thickest piece of beef. It should register at least 145°F (63°C). If not, continue cooking for another 30 minutes and check again.
Turn off the slow cooker and let the beef rest in the hot liquid for at least 3 minutes. This resting period ensures the meat stays juicy and tender.
Spoon a generous portion of creamy whipped mashed potatoes onto each plate. Ladle the beef, carrots, potatoes, and rich buttery au jus over the top. Serve hot.

Contains: milk, gluten

Estimated nutrition per serving

Calories: 520
Protein: 35 g
Carbohydrates: 30 g
Fat: 28 g

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

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This recipe is based on a short cooking video and is published under the pen name Clara Weller. It was checked before publication, but errors can slip through. Nutrition, when shown, is an estimate. Read more in our editorial policy and on our food safety page.