Slow Cooker Roast Beef Sandwiches with homemade horseradish that take less than two hours from start to finish and taste amazing!
This recipe takes my super easy Slow Cooker Roast Beef and turns it into the best sandwiches ever with my horseradish dressing! Seriously, you will think they came from a fancy bistro, they are SO good!
Sabrina’s Slow Cooker Roast Beef Sandwiches
When I first created this site, I was so excited to bring readers my easy, crazy tender slow cooker recipe for roast beef! I love that you can cook beef so evenly and perfectly in a crockpot – the crust is amazing, and the meat is cooked to a perfect medium temperature. It quickly became a top recipe, followed by this delicious sandwich to serve the leftovers. Years later, both recipes remain reader (and personal) favorites and for good reason! You can always make these sandwiches with thick-cut deli roast beef, but if you can, you should definitely try them with homemade roast beef too. Follow the link in the recipe card for the meat or see the abridged directions below in this post.
Recipe Card


Ingredients
- 2 pounds Slow Cooker Roast Beef , thinly sliced
- 4 bakery style hoagie rolls
- 2 tablespoons butter
- lettuce
- tomatoes sliced
- 2 tablespoons prepared horseradish
- 1 tablespoon cider vinegar
- 1/4 cup mayonnaise
- 1/2 cup sour cream
Instructions
- In a small bowl add the prepared horseradish, cider vinegar, mayonnaise and sour cream and mix well.
- Butter the buns and put them into the toasted oven to toast.
- Spread the horseradish sauce onto the rolls.
- Layer on the lettuce and tomatoes.
- Top with Roast Beef slices and and the top roll.
Nutrition
Table of contents
More About this Recipe:
You may be wondering why this post is separate from my original slow cooker roast beef recipe. Well, for a couple of reasons. The serving style is different here since it is sliced thinly and served at room temperature versus served plated with sides like prime rib. Secondly the horseradish dressing didn’t fit in the original recipe card. And finally, I just wanted this beautiful sandwich with its amazing sauce to get its day in the sun! I hope you enjoy it as much as I do!
Chef’s Note: Horseradish
So, let’s talk horseradish for a moment. I love keeping horseradish in the fridge because it adds a huge punch of flavor to my sandwiches. I don’t use the horseradish “pure,” though. I have been a bit of a spice wimp since I had kids, so I mix my horseradish with mayonnaise and sour cream to mellow it out. The recipe for the horseradish in this sandwich is actually for a horseradish “sauce,” which takes prepared horseradish and mellows it out. You can, of course, use the prepared horseradish on the sandwich alone, too.
Slow Cooker Roast Beef
Time needed: 1 hour and 30 minutes
- Season
Rub a 5 lb chuck roast with 2 teaspoons salt, ½ teaspoon pepper and 2 cloves of minced garlic.
- Heat Oil
Heat a large pot over high heat with 1 tablespoon of vegetable oil.
- Sear
Sear the beef of on all sides, about 3-4 minutes on each side.
- Transfer
Transfer the meat and the drippings to the slow cooker insert.
- Cook
Cook on low heat with the lid for 90 minutes.
How to Assemble Sandwiches
- Add the prepared horseradish, cider vinegar, mayonnaise, and sour cream in a small bowl and mix well.
- Butter the buns and put them into the toasted oven to toast.
- Spread the horseradish sauce onto the rolls.
- Layer on the lettuce and tomatoes.
- Top with Roast Beef slices and the top bun enjoy.
More Tasty Slow Cooker Sandwiches




There’s no actual recipe for cooking the beef. Where is it??
Here it is 🙂 https://dinnerthendessert.com/slow-cooker-roast-beef-sliceable/
Excuse my ingnorance ? But do you serve the meat on this warm or chilled? Thank you! Looks delish! This will be our Father’s Day meal this year for sure!
I served mine at room temperature but you can serve it any way you’d like 🙂 This will be perfect for Father’s Day!!
Do you cook the roast beef in the slow cooker ?
Yes, I have a recipe for Slow Cooker Roast Beef (Sliceable!). Enter that into the search bar and it’ll take you there. The recipe so easy and comes out perfect!
What cut of beef did you use for this recipe?
I used a chuck roast 🙂
About how long did you let it cook and was it on high or low?
I let the roast beef cook on low for 90 minutes after searing the beef for about 3-4 minutes per side.
That horseradish sauce is everything! I simply cannot eat roast beef without horseradish and I am now craving this sandwich big-time.
You shouldn’t ignore that craving 😉
I am thinking my slow cooker can do my cooking today! Yum!
Smart decision! I’m right there with you!!
I am such a sandwich girl…I think I need to try this. And I have to mellow out horseradish too….it’s just too strong for me.
Let me know what you think after trying it!
This sandwich looks so sooo amazing! I love mayonnaise and roast beef sandwich! Is the best!
Thanks Catalina!
Mannnnnn…. this looks SO good! My husband would go crazy for this. 🙂
One of my very favorite flavor combinations is roast beef at horseradish. Can’t wait to try this one!
Nope. Just nope. I’m not gonna make it because I know I won’t be able to handle all the awesomeness! 😛
Do it…I have faith that you can handle it!