This slow cooker rosemary Dijon beef tenderloin is one of those set-it-and-forget-it dinners that still feels special enough for Sunday supper or having friends over. You literally brush Dijon mustard over a whole beef tenderloin, add just five more simple ingredients, and let the slow cooker do the work. The mustard, rosemary, and garlic melt into the meat as it cooks, giving you tender slices that disappear faster than anything else on the table. It’s a great way to make an elegant roast without hovering over the oven, especially on busy days with kids and activities.
Serve this beef tenderloin sliced thick with its juices spooned over the top. It’s wonderful with buttery mashed potatoes, roasted baby potatoes, or egg noodles to soak up the flavorful juices. Add a green vegetable like steamed green beans, roasted Brussels sprouts, or a simple side salad to round out the plate. Warm dinner rolls or crusty bread are great for sopping up the extra sauce. For a special touch, add a simple fruit salad or a pan of brownies for dessert to make it feel like a cozy family celebration.
Slow Cooker Rosemary Dijon Beef TenderloinServings: 6
Ingredients
2 to 2 1/2 pounds beef tenderloin, trimmed
1/3 cup Dijon mustard
1 tablespoon olive oil
1 tablespoon fresh rosemary, finely chopped (or 1 teaspoon dried rosemary)
3 cloves garlic, minced
1 teaspoon kosher salt
1/2 teaspoon black pepper
Directions
Pat the beef tenderloin dry with paper towels so the mustard will stick well. Place the tenderloin directly into the slow cooker insert, laid out as flat as it will comfortably fit.
In a small bowl, stir together the Dijon mustard, olive oil, chopped rosemary, minced garlic, kosher salt, and black pepper until you have a smooth, fragrant paste.
Using a pastry brush or the back of a spoon, brush the Dijon mixture all over the surface of the raw beef tenderloin in the slow cooker. Make sure to coat the top, sides, and any exposed ends so every bite picks up flavor. This should look like a thick, even layer of mustard being brushed over the meat right in the slow cooker.
Cover the slow cooker with the lid and cook on LOW for 2 to 3 hours, or until the internal temperature reaches about 130°F for medium-rare or 140°F for medium when checked with an instant-read thermometer in the thickest part. Try not to lift the lid too often so the heat stays steady.
Once the beef reaches your desired doneness, carefully transfer the tenderloin to a cutting board and tent loosely with foil. Let it rest for 10 to 15 minutes so the juices settle back into the meat.
While the beef rests, skim off any excess fat from the top of the juices in the slow cooker. You can leave the juices as-is for a light sauce or simmer them in a small saucepan on the stove for 5 to 10 minutes to reduce slightly for a richer flavor.
Slice the rested beef tenderloin into 1/2-inch thick slices. Arrange on a serving platter and spoon some of the warm rosemary Dijon juices over the top. Serve right away, passing extra juices at the table.
Variations & Tips
For picky eaters who aren’t crazy about mustard, you can cut the Dijon down to 1/4 cup and add 1 tablespoon of honey to make it a bit milder and slightly sweet. If your family prefers stronger herbs, add an extra teaspoon of rosemary or a pinch of dried thyme. To make the dish feel even more complete, scatter thick-sliced onions or baby carrots in the bottom of the slow cooker before adding the tenderloin; they’ll soak up the flavorful juices as they cook. For a creamier finish, whisk 1 to 2 tablespoons of softened butter into the hot cooking juices just before serving to create a simple pan sauce. If you don’t have beef tenderloin, this same method works with a similar-sized pork tenderloin—just plan on slightly longer cook time and check for doneness at 145°F. Leftovers make wonderful sandwiches: chill the beef, slice it thin, and serve on rolls with a little extra Dijon and a slice of cheese for an easy next-day lunch.
