Name: Easy Slow Cooker Beef and Broccoli
Prep time: 15 min
Cook time: 2 h 10 min
Total time: 2 h 25 min
Ingredients: 1 1/2 to 2 lb flank steak (or sirloin), sliced thin against the grain, about 1/4 inch thick; 1/2 cup low-sodium soy sauce; 1/4 cup hoisin sauce; 2 tbsp brown sugar; 3/4 cup beef broth; 3 to 4 cloves garlic, minced; 1 tsp fresh ginger, minced; 2 tsp toasted sesame oil; 3 tbsp cornstarch; 3 tbsp cold water; 6 cups broccoli florets (about 1 medium head); Cooked white rice, for serving

My crockpot has been sitting on the counter all week, and last Tuesday it finally earned its spot. I pulled out this slow cooker beef and broccoli at 5:45, spooned it over rice, and every kid at the table cleaned their bowl without a single complaint.

That almost never happens on a Tuesday.

The trick that took me a few tries to figure out: the beef goes in for only 1 1/2 to 2 hours, not the usual all-day stretch. Thin-sliced flank steak isn’t a tough braising cut.

Hold it for six hours and you’ll get stringy, gray ribbons instead of tender strips.

Broccoli goes in at the very end, too. Thirty minutes on HIGH is all it needs to stay bright green and a little crisp.

That’s the version my family actually asks for again.

Prep: 15 minutes · Cook: 2 hours 10 minutes · Total: about 2 hours 25 minutes · Serves: 6

↓ Jump to the recipe

How do you make slow cooker beef and broccoli sauce thick?

Stir together equal parts cornstarch and cold water, then pour the slurry into the pot when you add the broccoli and switch the slow cooker to HIGH. The HIGH setting is what activates the cornstarch. On LOW, the slurry just sits there and the sauce stays thin. Give it 30 to 40 minutes and it thickens up nicely.

The Method, in Plain English

Slicing the beef thin, about 1/4 inch across the grain, means the fibers are already short before cooking starts, so the meat turns tender in 1 1/2 to 2 hours instead of needing a long braise.
A 1:1 cornstarch-to-water slurry, stirred into cold water before it touches the pot, disperses the starch evenly so the sauce thickens without lumps. Ruhlman’s ratio guide confirms the 1:1 by volume as the standard slurry proportion.
Broccoli added in the last 30 to 40 minutes on HIGH stays green and holds a slight bite. Broccoli that cooks from the start turns an olive color and goes completely soft.

The first time I made this, I added the broccoli at the beginning because I figured it would be fine. It was not fine.

Forty-five minutes of mush later, I learned to set a timer and add it at the end.

Why I Keep Coming Back to This One

The sauce tastes like takeout and uses pantry staples you probably already have.
Active prep is about 15 minutes, and the slow cooker does the rest.
It feeds six people over rice for well under the price of a delivery order.
The leftovers reheat beautifully the next day for lunch.

What Goes Into Slow Cooker Beef And Broccoli

1 1/2 to 2 lb flank steak (or sirloin), sliced thin against the grain, about 1/4 inch thick
1/2 cup low-sodium soy sauce
1/4 cup hoisin sauce
2 tbsp brown sugar
3/4 cup beef broth
3 to 4 cloves garlic, minced
1 tsp fresh ginger, minced
2 tsp toasted sesame oil
3 tbsp cornstarch
3 tbsp cold water
6 cups broccoli florets (about 1 medium head)
Cooked white rice, for serving

A Few Notes on the Ingredients

Use low-sodium soy sauce here, and don’t swap it for regular. With a full 1/2 cup going into the pot, regular soy sauce will make the finished dish far too salty to eat.

Both Spend With Pennies and Tasty specify low-sodium for exactly this reason.

Flank steak is the first choice because it slices cleanly and stays tender at this short cook time. Sirloin and boneless chuck roast also work well.

If you use chuck, cut it into thin strips rather than chunks so it cooks through in the same window. Beef stew meat in small pieces is a budget option that works fine.

Toasted sesame oil is a finishing flavor, not a cooking fat. It goes into the sauce raw, and the slow heat carries the aroma through the whole dish.

Plain sesame oil is much milder and won’t give you the same result, so look for the word “toasted” on the bottle.

Making Slow Cooker Beef And Broccoli, Step by Step

Slice the beef. Cut the flank steak against the grain into strips about 1/4 inch thick. This is the step that makes or breaks the texture, so take your time with it. Thin, cross-grain slices mean short muscle fibers that turn tender fast, until each strip bends easily when you pick it up.
Mix the sauce. In the insert of your slow cooker, whisk together the soy sauce, hoisin sauce, brown sugar, beef broth, garlic, ginger, and sesame oil until the sugar dissolves and the mixture looks uniform, about 1 minute of stirring.
Add the beef. Drop the sliced beef into the sauce and toss to coat every strip. Spread it out as evenly as you can so the pieces aren’t all stacked in one corner, which would slow the cook unevenly.
Cook on LOW. Put the lid on and cook on LOW for 1 1/2 to 2 hours, until the beef strips are cooked through and tender when you press one with a spoon. Don’t push past 2 hours or the meat starts to tighten up.
Make the slurry. In a small bowl, whisk the cornstarch with the cold water until completely smooth with no white lumps at the bottom. It has to be cold water, not warm, so the starch disperses before it hits the heat.
Add broccoli and slurry. Pour the slurry into the pot, add the broccoli florets, and stir everything together so the florets get coated in sauce. Switch the slow cooker to HIGH.
Finish on HIGH. Cook on HIGH for 30 to 40 minutes, until the sauce has thickened enough to coat the back of a spoon and the broccoli is bright green and just tender when pierced with a fork. If the sauce looks thin at 30 minutes, give it another 10.
Serve over rice. Spoon the beef and broccoli over cooked white rice while it’s still steaming hot from the pot.

Tips for Success

Don’t use regular soy sauce in place of low-sodium. The dish will be too salty to fix, and there’s no easy way to walk that back once it’s in the pot.
If your broccoli florets are large, cut them smaller before they go in. Big chunks won’t cook through in 30 to 40 minutes and you’ll end up with raw centers.
The slurry must be mixed with cold water first, every time. Cornstarch stirred directly into a hot liquid clumps immediately and you’ll spend ten minutes chasing lumps around the pot.
Boneless chuck roast works as a beef swap, but slice it thin like the flank steak rather than leaving it in chunks. Chunks need more time and the sauce will be done before the meat is.
I don’t measure the sesame oil exactly anymore, and I’m not going to pretend I do. Two teaspoons is the starting point, but a little extra never hurt this dish.

Storage and Make-Ahead

Leftovers keep in a covered container in the fridge for up to 4 days. Store the beef and broccoli separately from the rice so the rice doesn’t absorb all the sauce overnight.

To reheat, add a splash of water or broth to the beef and broccoli and warm it in a skillet over medium heat, stirring until the sauce loosens back up and everything is heated through. The microwave works too, just cover it so the sauce doesn’t splatter.

This dish freezes well without the broccoli. Freeze the beef and sauce in a zip-top bag for up to 3 months, then thaw overnight in the fridge and add fresh broccoli when you reheat it.

Broccoli that’s been frozen and reheated goes soft, so fresh is worth it.

Rounding Out the Meal

Steamed white rice is the natural base, since the sauce is built to soak into it and every bite stays saucy.
Fried rice works even better if you have leftover rice in the fridge, since day-old rice fries up drier and doesn’t get soggy under the sauce.
A simple cucumber salad with rice vinegar cuts through the richness of the hoisin and gives the plate a cool, crisp contrast.
Plain steamed jasmine rice with a drizzle of the extra sauce from the pot is the version my kids ask for most.

Tools You’ll Need

A 6-quart slow cooker, large enough to hold the beef in a single loose layer so it cooks evenly rather than steaming in a pile.
A sharp chef’s knife, because slicing raw flank steak thin and against the grain is much easier with a blade that doesn’t drag.
A cutting board with some grip, since you’ll be slicing against the grain and a sliding board makes it harder to keep the cuts consistent.
A small bowl and a fork or small whisk for the slurry, so you can confirm there are no lumps before it goes into the pot.

Questions I Get About Slow Cooker Beef And Broccoli

Can I cook slow cooker beef and broccoli on HIGH instead of LOW? You can cook the beef on HIGH for about 1 hour instead of LOW for 1 1/2 to 2 hours, but watch it closely. Thin-sliced flank steak overcooks quickly on HIGH and can go tough before you know it.

Why is my sauce still thin after the cooking time? The most common reason is that the slow cooker was left on LOW when the slurry and broccoli went in. Cornstarch needs real heat to thicken, so switch it to HIGH and give it the full 30 to 40 minutes.

Can I use frozen broccoli? Yes, but add it straight from frozen and expect it to release some water into the sauce. The sauce may need an extra 10 minutes on HIGH to tighten back up, and the texture will be softer than fresh.

What cut of beef works best for this recipe? Flank steak is the top choice because it slices cleanly and stays tender at a short cook time. Sirloin is a close second. Boneless chuck roast sliced thin also works well and is often cheaper per pound.

Is this recipe very salty? With low-sodium soy sauce and the hoisin, the salt level is well-balanced for most palates. If you’re sensitive to sodium, start with 1/3 cup soy sauce and taste before serving.

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