Cowboy Butter Asparagus Sirloin Tips: 5-Ingredient Crockpot Dinner Step-by-step instructions

Before you start

Before starting, cut the sirloin tips into uniform 2-inch pieces if they are not already. Trim the asparagus spears, snapping off the woody ends. Smash the garlic cloves to release their flavor.

Measure the au jus mix. Have the cowboy butter at room temperature or slightly softened for easier placement. No other prep is needed; the slow cooker does the rest.

Instructions

Layer and Season

1. 1Layer the Ingredients
   Place the hand-cut top sirloin steak tips in the bottom of the slow cooker in an even layer. Lay the fresh asparagus spears over the beef, then scatter the smashed garlic cloves on top. The beef should be fully covered by the other ingredients so it stays moist during cooking.
   Look for The slow cooker is filled with raw beef, asparagus, and garlic, ready for the butter and seasoning.
   Tip Cut any large steak tips into uniform 2-inch pieces so they cook evenly.
2. 2Add the Butter and Au Jus
   Place the two sticks of garlic-herb cowboy butter on top of the beef and vegetables. Sprinkle the au jus mix evenly over everything. Do not stir; the butter will melt and create a rich sauce as the slow cooker heats.
   Look for The butter sits in golden sticks over the beef, and the au jus mix forms a savory crust on top.
   Tip For a more intense flavor, use salted butter and adjust salt at the end, as the au jus mix already adds saltiness.

The slow cooker is filled with raw beef, asparagus, and garlic. The butter sits on top, and the au jus mix forms a savory crust. The ingredients are raw and ready for the slow cooker to work its magic. The beef should be in an even layer, and the asparagus and garlic should cover it completely.

Slow Cook to Tender

3. 3Slow Cook on Low
   Cover the slow cooker and cook on LOW for 6 to 7 hours, or until the beef is fork-tender. Avoid opening the lid during the first few hours to keep the heat steady. The butter will melt into a bubbling au jus, and the beef will become tender enough to shred with a fork. Let it rest for 3 minutes before slicing.
   Look for The sauce is bubbling gently, and the aroma of garlic and herbs fills the kitchen.
   Safe temperature 145°F (63°C) internal temperature (steaks, chops and roasts)
   Tip If the slow cooker runs hot, check at the 5-hour mark; some models cook faster than others.

As the slow cooker heats, the butter melts, creating a bubbling golden sauce that coats the beef and asparagus. The aroma of garlic and herbs fills the kitchen.

The beef is visibly cooking, and the sauce is gently simmering. Check that the beef is becoming tender, but avoid opening the lid too often.

Finish and Serve

4. 4Check for Tenderness
   Test the beef by piercing a piece with a fork. It should slide in easily and the meat should be tender but still hold its shape. If it is not tender enough, continue cooking for 30 minutes more. The asparagus should be tender but not mushy. Let it rest for 3 minutes before slicing.
   Look for The beef yields easily to a fork, and the asparagus bends slightly but is not falling apart.
   Safe temperature 145°F (63°C) internal temperature (steaks, chops and roasts)
   Tip If the sauce seems thin, remove the beef and vegetables and simmer the sauce on the stovetop to reduce.
5. 5Rest and Serve
   Turn off the slow cooker and let the beef rest in the hot sauce for at least 3 minutes before serving. This allows the juices to redistribute. Serve the sirloin tips and asparagus over creamy mashed potatoes, spooning plenty of the garlic-herb butter au jus over the top.
   Look for The beef rests in the glossy, bubbling sauce, ready to be ladled over mashed potatoes.
   Safe temperature 145°F (63°C) internal temperature (steaks, chops and roasts)
   Tip For a thicker sauce, whisk 1 tablespoon cornstarch with 2 tablespoons cold water and stir into the hot liquid.

The beef is fork-tender, and the asparagus is tender but not mushy. The sauce is thick and glossy, with a rich buttery sheen. The beef rests in the hot sauce, absorbing the flavors. When served over mashed potatoes, the dish is complete, with the sauce generously spooned over the top.

Common mistakes

One common mistake is lifting the lid too often during cooking, which lets out heat and extends the cooking time. Another is overcooking the asparagus, which turns it mushy; add it later if your slow cooker runs hot.

Also, resist the urge to stir the ingredients, as layering helps the butter melt and the seasonings distribute evenly. Finally, don't skip the rest time—it's key to juicy meat.

How to tell it’s done

The dish is done when the beef is fork-tender, meaning a fork easily pierces a piece and the meat yields without resistance. The internal temperature of the beef should read at least 145°F (63°C) for medium-rare, but for slow-cooked tenderness it will likely be higher.

Let the beef rest in the sauce for at least 3 minutes before serving to allow the juices to redistribute. The asparagus should be tender but still have a slight bite.

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