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Roast Beef in the Slow Cooker

Now with the fall season upon us, it is time for getting out the Slow Cooker. With just a little planning and fore thought, you can have your supper in the slow cooker all day. When you come home from a busy day the aroma will inspire you to do a few final touches, and supper is DONE! Thursday for me is a full day so I like to have my supper ready when I get home. This recipe is something that I came up with using leftover spaghetti sauce. It makes a wonderful gravy that is not a strong tomato flavor. I like to use leftovers in soups and other dishes so that nothing goes to waste.
  • a cut of your favorite roast beef ( I used an inside round), size depending on how many you want to serve
  • a chopped onion
  • 2 cups sliced mushrooms
  • 2 cups of left over spaghetti sauce
  • 2 tbsp. cornstarch
  • 1/2 cup of cold water
  1. Place your roast in the slow cooker.
  2. Add onions, mushrooms, and spaghetti sauce.
  3. Cook on low for 8 hours.
  4. Remove roast and cover while you make the gravy.
  5. Turn slow cooker to high and mix the cornstarch with the cold water.
  6. Add to the gravy and stir well.
  7. Bring to a boil and simmer 2 minutes.
  8. Add roast beef (that has been sliced at an angle and against the grain) back to the gravy.
  9. Serve with mashed potatoes and your favorite side vegetable dish.


  1. So you put all the ingredients in the crock pot except the cornstarch and water? Looks like that goes in last when you make the gravy? Also, did you say you used a round beef roast? Thanks for you help with this. It looks delicious and I want to make it.

  2. This looks wonderful Char..and it is the season for crock pot meals!

  3. lori
    i put everything in and at the end i mixed the cornstarch with the water and thickened it a bit.......
    i think you can use what ever roast you want, i use what i buy on sale.
    you can use a leaner cut, because of the gravy, i don't like using a fatty roast.....just a personal preference.

  4. mmmmmmm! This looks wonderful. Love crock-pot meals.

  5. You say that the size of the roast depends the number of servings, I believe I have a 6qrt crock, is there a certain ratio of meat weight to crock size that cooks better?

  6. looks yummy!

  7. Oh dear, I shouldn't have popped in as now I wish I was making your roast for supper...LOL!

  8. Oh Charlotte, this looks scrumptious. I am resolved to get my crock pot out more often.

  9. This recipe looks delicious. My favorite roast is a chuck roast. It was a lot of marbeling that gives a lot of flavor to the meat. The spaghetti sauce is an interesting twist - something a little different than the onion and mushroom gravy that I normally cook. Can't wait to try it.

  10. Smiles...I just took a roast out of the freezer, wondering what what I was going to do with it. I wonder no more. This looks delicious!

  11. This sounds really tasty and I have never had roast beef this way. I really must try this.

  12. Charlotte I'm so wanting to bite into this yummy looking dish!! Thank you...

  13. The old fashioned slow cooking has always been the most delicious for me. Thumbs up for this recipe.

  14. Looks good. Plan to try it for Sunday dinner tomorrow.

  15. Just finished cleaning up from supper, made the roast, yummm...I also added garlic


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