When I visit home, one of my favorite comfort foods is an open faced roast beef sandwich. This crowd-pleaser is made with just a few ingredients that provide layers of flavor and texture. I make the roast beef in a slow cooker for an easy hands-off recipe with minimal prep. It comes out hot, juicy, and perfectly tender!
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Brace yourselves: I am about to blow your mind with this delicious open faced roast beef sandwich recipe! Crusty bread is topped with creamy mashed potatoes, slow cooker roast beef, and a sprinkling of cheese and au jus. I love the way the bread sops up the au jus!
What’s in This Open Faced Roast Beef Sandwich Recipe?
- Roast Beef: I recommend using chuck or rump roast for this recipe. Since you’re slow cooking the beef, you want a fairly tough cut that will soften without falling apart. After a few hours in the crock pot, it will be perfectly tender.
- Au Jus Seasoning Mix: This dry mix adds so much flavor to the beef as it cooks. I usually use McCormick Au Jus Gravy, but any brand will work.
- Italian Salad Dressing Mix: Adds classic Italian flavor to the meat. I used Good Seasons, but again, any brand will work. In a pinch, Italian seasoning also works, but it doesn’t provide as much salt so the flavor may be more muted.
- Beef Broth: Low-sodium beef broth keeps the meat super moist as it cooks.
- Mashed Potatoes: Add a creamy element to the sandwiches.
- Bread: I recommend using a thick-cut Texas toast-style bread for these sandwiches. It holds up well to the juicy beef.
- Cheese: I love gruyere for these sandwiches! It tastes amazing melted over the beef and slathered with au jus. But you could also use Swiss cheese or any cheese you really love.
Tips for Success
- Each pound of roast beef will make about 2 sandwiches.
- Be sure to spray the slow cooker with nonstick spray before adding the other ingredients.
- For a slightly healthier swap, try using mashed cauliflower instead of potatoes.
- Don’t assemble the sandwiches until right before serving–the juices will make the toast soggy.
- These open faced sandwiches are mouth-wateringly delicious when served hot, but they taste great cold too. Especially if you’re eating leftovers for lunch the next day!
- These sandwiches are also great with mustard cream sauce or mayonnaise!
How to Store and Reheat
I recommend storing the components of these open faced sandwiches separately, since they can become soggy if left fully assembled. Store the beef and potatoes in separate airtight containers for up to 4 days or in the freezer for up to 3 months. Let thaw overnight in the refrigerator before reheating the beef in the microwave and toasting the bread to serve.
Serving Suggestions
These hot roast beef sandwiches are a pretty hearty dish on their own. Piled up with mashed potatoes, slow cooked beef, cheese, and au jus sauce, you have a full meal here. But you could serve up extra mashed potatoes on the side, make some potato wedges, add some baked beans, or add some spicy broccoli to get your veggies in. As an added bonus, any leftovers can be used for beef au jus sandwiches!
Open Faced Roast Beef Sandwich Recipe
Equipment
Ingredients
- 5 pounds beef roast such as chuck or rump
- 4 ounces au jus seasoning mix (2 packages)
- 4 ounces dry Italian salad dressing mix (2 packages)
- 32 ounces low-sodium beef broth
- 4 cups mashed potatoes (click for recipe)
- 8 slices bread thick and crusty, such as Texas Toast
- ½ cup freshly shredded gruyere cheese
Instructions
- Spray your crockpot with nonstick spray. Place the beef roast inside and sprinkle with the four packets of seasoning.5 pounds beef roast, 4 ounces au jus seasoning mix, 4 ounces dry Italian salad dressing mix
- Pour the beef broth over the roast.32 ounces low-sodium beef broth
- Cook on high for 6-8 hours or until tender.
- When cooked, strain the broth into a bowl and reserve.
- Shred or slice the beef into small bite-sized sections. Discard away any fat and gristle.
- Prepare the mashed potatoes.4 cups mashed potatoes
- Toast the bread. For extra-thick slices, broil for 2-4 minutes until golden.8 slices bread
- Assemble the open-faced sandwiches by placing the toasted bread on a plate and topping it with mashed potatoes. Add a generous portion of the shredded/sliced beef. Drizzle a couple of spoonfuls of the reserved au jus over the meat and sprinkle with gruyere cheese.½ cup freshly shredded gruyere cheese
- Serve with a knife and fork. Enjoy!
Video
Becky’s Tips
Nutrition information is automatically calculated, so should only be used as an approximation.
Did you make this? Leave a comment!
How to Make an Open Faced Roast Beef Sandwich Step by Step
Cook the Beef: Spray your crockpot with nonstick spray. Place a 5 pound beef roast inside and sprinkle with 4 ounces each of au jus seasoning and dry Italian salad dressing mix. Pour 32 ounces of beef broth over the roast, and cook on high for 6-8 hours or until tender.
Shred the Beef: When cooked, strain the broth into a bowl and reserve. Shred or slice the beef into small bite-sized sections. Discard away any fat and gristle.
Assemble the Sandwiches: Prepare 4 cups of mashed potatoes. Toast 8 slices of bread. For extra-thick slices, broil for 2-4 minutes until golden. Assemble the open-faced sandwiches by placing the toasted bread on a plate and topping it with mashed potatoes. Add a generous portion of the shredded/sliced beef. Drizzle a couple of spoonfuls of the reserved au jus over the meat and sprinkle with ½ cup of freshly shredded gruyere cheese. Serve with a knife and fork. Enjoy!
Recipe specifies to cook on HIGH 6-8 hours. Is a LOW setting for a longer period of time (if so how long) not recommended & if so, is it because the meat will be too dry? I’m out of the house for 9 hours a day during the week so 6-8 hrs does not work since my crockpot does not have the delayed cooking option. Recipe still looks amazing & I definitely going to try.
Low for 9 hours should work!
Wow! I could almost read the recipe. I was hoping maybe you could cram some more crap on this page so that there were 0 pixels with the actual recipe. Absolute deumoster fire.
Hi! As you can see in the picture, there is a “jump to recipe” button that will take you directly to the recipe card! Hope that helps!
I tried to update my post because it was a really good recipe and I honestly don’t want to hurt your business with a bad review.
But man, the site is frustrating. I found that button and it took me to the attached view. There is roughly 15% of the screen available for reading.
Feel free to delete my original comment to up your rating.
We’re sorry for your frustration! The “jump to recipe” button does take you to a place just above the recipe card, so you do have to scroll just a little bit more to get there. Once at the recipe card, you can print or save it so that you have an ad-free version for next time!!
Click on the AA and it goes into reader mode for anything you are looking at on the ol interweb. Just an fyi so you don’t have to leave comment like this anymore 😉
If I wanted to use an instapot instead of a slow cooker would it work as well?
We think so! We would probably do 1½-2 hours on the stew function.
Would you mind sharing your favorite brand names of Italian seasoning packets as well as you au jus packets? I’d love to try the exact ones you use if possible.
I use ones that I find at my local supermarket so the brand may not be where you are! All are great!
Looks amazing I can’t wait to try
Thanks Shirley!
I am making this right now! One question… shouldn’t the meat be fully covered with fluids? I’m using a serloin roast and its only about half submursed in the broth. Should I add water, if so how much? Thanks!
Hey Caitlin, yes you could either add more water or more broth so that its covered. Hope that helps! Thanks so much for stopping by!
I’m making this recipe right now. You mention a “box” of beef broth, but not a size. Is it one of the big boxes (32oz) or the smaller size like from Swansons?
Hey Jeanette,
I use the 32 oz. box of broth. Thank you for trying one of our recipes and please let us know if you have further questions. Susie (Becky’s mom).