Cowboy Butter Flank Steak Slow Cooker Dinner Step-by-step instructions

Before you start

Before you start, make sure you have a 6-quart slow cooker. Slice the flank steak against the grain into thin strips, about 1/4-inch thick. If using fresh pearl onions, peel them by blanching in boiling water for a minute, then slipping off the skins.

If using frozen pearl onions, thaw them first. Crinkle-cut carrots are available in the produce section, but you can also cut regular carrots into coins. Measure out all your ingredients and have them ready to add to the slow cooker.

Instructions

Layer and Season

1. 1Layer the Ingredients
   Place the sliced flank steak strips in the bottom of a 6-quart slow cooker. Scatter the pearl onions and crinkle-cut carrots over the beef. Place the sticks of garlic-herb cowboy butter on top, then sprinkle the dry au jus mix evenly over everything. Do not stir.
   Look for The beef, onions, and carrots should be evenly layered, with the butter and au jus mix on top.
   Tip For even cooking, try to spread the beef in a single layer if possible.

At the end of this phase, the slow cooker will contain raw beef, onions, carrots, butter, and au jus mix. The ingredients should be evenly distributed, with the butter and seasoning on top.

The raw beef will look pink and the vegetables will be crisp. There's no need to stir; the heat will work everything together as it cooks.

Slow Cook to Tender

2. 2Slow Cook Until Tender
   Cover the slow cooker and cook on LOW for 6 to 7 hours, or on HIGH for 3 to 4 hours, until the beef is fork-tender and easily shreds. The butter will melt and combine with the au jus mix to create a rich, savory sauce. Let it rest for 3 minutes before slicing.
   Look for The beef should be deeply browned and tender, and the sauce will be bubbling and aromatic.
   Safe temperature 145°F (63°C) internal temperature (steaks, chops and roasts)
   Tip Avoid lifting the lid during cooking to keep the heat steady.

After several hours, the slow cooker will be filled with a bubbling, aromatic sauce. The beef should be deeply browned and tender, and the onions and carrots will be soft and glazed. The kitchen will smell of garlic, herbs, and beef. The sauce should be a rich golden brown and the beef should easily shred with a fork.

Rest and Serve

3. 3Rest and Serve
   Turn off the slow cooker and let the beef rest in the sauce for at least 10 minutes. Use a slotted spoon to transfer the beef, onions, and carrots to a serving platter or over mashed potatoes. Spoon some of the au jus over the top before serving.
   Look for The beef should be tender and moist, and the sauce should coat the back of a spoon.
   Tip For a thicker sauce, whisk 1 tbsp cornstarch with 2 tbsp cold water and stir into the slow cooker before serving.

After resting, the beef will be even more tender and the sauce will have settled. The platter should be piled with juicy beef, sweet onions, and carrots, all coated in the glossy au jus. The sauce should be thick enough to coat the back of a spoon, and the aroma will be irresistible.

Common mistakes

One common mistake is lifting the lid to check on the food. Each time you open the slow cooker, heat escapes, which can extend cooking time. Another mistake is overcooking the beef, which can make it dry and stringy.

Stick to the recommended cooking times and check for doneness at the minimum time. Also, don't skip the resting step—letting the beef rest in the sauce helps it retain moisture and allows the flavors to meld.

How to tell it’s done

The beef is done when it is fork-tender and easily pulls apart. To check, insert a fork into a piece of steak and twist; it should shred with little resistance.

The internal temperature of the beef should reach at least 145°F (63°C) for food safety, but because it's cooked low and slow, it will likely be well above that. The sauce should be bubbling and slightly thickened, and the vegetables should be soft but not mushy.

• Steaks, chops and roasts: 145°F (63°C) in the thickest part, then a 3-minute rest