Slow Cooker French Onion Roast is simple yet full of flavor. Perfect comfort food on a chilly winter night.
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I really love fresh summer food, but I’ve got to tell you, not much beats a roast that’s slow cooked for hours on a chilly night.
For me, that’s the ultimate in comfort food.
Ingredients for French Onion Roast
How to Make French Onion Roast
Start by heating a large skillet or dutch oven over medium-high heat. Add the vegetable oil.
Pat the roast dry with a paper towel. Season both sides with salt and pepper. Add to the hot skillet and sear, about 2 to 3 minutes per side, until a crust forms.
Once seared, add to your slow cooker. While the pan is still hot, add the beef broth and scrape the bottom of the pan with a wooden spoon to get all the bits off. There is major flavor there so don’t miss out on them.
Remove from heat and whisk in the French onion soup mix, Worcestershire sauce, Dijon mustard and butter. Pour over the roast in the slow cooker.
Set to cook for 4 to 5 hours on high or 6 to 8 hours on low. Once it’s fall apart tender, remove from the slow cooker to a plate.
In a small bowl whisk together cornstarch and water to make a slurry. Stir into the slow cooker then place the roast back. Cook another 10 minutes to thicken the liquid into a gravy.
Reheats Like a Dream
Sometimes leftovers fall flat but this French Onion Roast reheats and tastes just as good, if not better, than on the first day.
And listen, this is coming from someone who is not keen on leftovers. I mean I eat them, but I don’t love it.
So this would be a great option for meal prepping lunches. Or to make a big batch and eat throughout the week if you like that kind of thing.
What to Serve with French Onion Roast
My immediate go to for this roast is mashed potatoes or thick egg noodles. Basically anything you can drench in the gravy.
To bring in a little health, roasted carrots or shaved brussels sprouts salad would be a great accompaniment.
A big glass of red wine would round things out for the ultimate in cozy comfort meal.
More Cozy Dinner Ideas:
French Onion Roast
- Slow Cooker
- 1 Tbsp. vegetable oil
- 1 tsp. kosher salt
- 1 1/2 tsp. black pepper, divided
- 2 1/2 lb. chuck roast
- 1 pkg. onion soup mix
- 1 14.5 oz. can beef broth
- 1 Tbsp. worcestershire sauce
- 1 Tbsp. Dijon mustard
- 2 Tbsp. butter
- 2 Tbsp. cornstarch
- 2 Tbsp. cold water
- Heat a large skillet over medium-high heat. Season roast with kosher salt and 1 teaspoon black pepper. Add vegetable oil to hot skillet. Add roast and sear each side, about 2 mintues per side.
- Meanwhile, add soup mix, beef broth, worcestershire sauce, Dijon mustard, butter and remaining 1/2 teaspoon pepper. Whisk well. Once done searing the roast, add it to the slow cooker. Flip so both sides get coated in the sauce.
- Cook on low for 6 to 8 hours or high for 4 to 5 hours.
- After time has elapsed, remove the roast from the slow cooker to a plate. In a small bowl, whisk together the cornstarch and cold water. Add to slow cooker and whisk well. Return roast to slow cooker and cook another 10 minutes, until sauce is thickened and glossy.