Roast Beef Sandwiches Made Easy with Slow Cooking
One of our favorite dinners has always been pot roast, but I’m never quite sure if we enjoy the roast more at dinner, or the sandwiches that come later. In fact, sometimes I’ll skip the pot roast altogether and cook a top or bottom round roast specifically for thinly sliced, slow-cooked roast beef sandwiches. That’s exactly what this post is about.
Why Top or Bottom Round Works for Roast Beef Sandwiches
Top round or bottom round roast is lean, budget-friendly, and holds up well to slow cooking. Unlike fattier cuts, these roasts slice beautifully once cooked and cooled, making them perfect for thin, tender slices that pile high on a sandwich. They don’t fall apart like a chuck roast would, so you get neat slices that fit between bread without crumbling. Plus, slow cooking adds the tenderness these lean cuts need, while still giving you that classic roast beef flavor.
Season and Sear for Flavor
First things first—give your roast a good sprinkle of seasoning. I just grabbed the basics: salt, pepper, garlic powder, and onion powder. Nothing fancy, but it works every time. Then, heat up a little olive oil in a heavy pan and sear the roast on all sides. You don’t want to skip this step—it’s what gives the meat that deep, rich flavor. If you’d rather keep things fresh, you can always toss in a chopped onion and some garlic cloves instead. Either way, the kitchen is going to smell amazing.
From Roast to Au Jus
Once the roast is well-seasoned, I sear it right in my Dutch oven with a little olive oil — no need for an extra pan. After it’s browned on all sides, cover it and pop the Dutch oven into the oven. Start at a high temperature to lock in that crust, then turn the heat down to around 250°F and let it roast slowly. Mine usually takes a couple of hours at least, and keep in mind it will continue to cook just a bit after you pull it out.
For the best results, let the roast cool completely before slicing. Even better, refrigerate it overnight and slice it the next day with a super sharp knife. Along the way, baste now and then with the juices, and don’t toss those drippings — they’re gold. Use them for au jus to dip roast beef sandwiches on toasted French bread, or make a quick gravy for open-faced sandwiches with mashed potatoes, one of our family’s favorite comfort meals when the weather turns chilly.
Slice It Thin & Build the Sandwich
When the roast has cooled, slice it thin—perfect for piling high on sandwiches. I always do a little taste test here, and more often than not, I end up sprinkling on a touch more salt and pepper. For the sandwiches, we like to whip up a simple spread of mayonnaise mixed with mustard. Add lettuce and tomato, and you’ve got a classic that never fails. Toasted bread or plain, either works. And of course, every good roast beef sandwich deserves a side—homemade onion rings are one of our favorites (you’ll find the link below).
Dutch Oven or Not?
I get asked sometimes if you really need a cast iron Dutch oven for cooking a roast like this. Honestly, I don’t use one—even though I love them. My go-to is a stainless steel Dutch oven–style pan with a lid. The main reason? Weight. A cast iron Dutch oven can tip the scales at 15 pounds or more before you even add the roast, and at this stage of the game, lighter is definitely safer (and easier) for me to move in and out of the oven. But if you have cast iron, by all means use it. You’ll absolutely love the way it cooks a roast.
So whether you’re using stainless steel or cast iron, the end result is the same—a tender, flavorful roast that slices up perfectly for the best homemade roast beef sandwiches.
What about you? Do you have a favorite way to cook a round roast — maybe a special seasoning mix, in the oven, on the stovetop, or even in the Instant Pot? I’d love to hear how you make yours!
