Subway-Style Roast Beef Sub Sandwich (Easy Homemade Copycat)

This Subway-style roast beef sub sandwich is an easy homemade version of a deli favorite. Made with thinly sliced roast beef, provolone cheese, crisp onions, fresh spinach, and sweet onion dressing, it comes together in just minutes.

As a former sandwich artist, I learned that a great roast beef sub is all about balance—fresh bread, properly layered ingredients, and just the right amount of toppings. This simple sub sandwich makes a satisfying lunch, picnic meal, or quick dinner when you want something hearty but easy to prepare.

My first job as a teenager was working as a sandwich artist at a local sub shop. Later I worked at two Subway locations, where every sandwich was built with precise ingredient portions and layering techniques. Those same methods inspired this homemade roast beef sub sandwich. This tasty submarine sandwich can be made with a variety of toppings, making it a super way to jazz up lunchtime. 

A good roast beef sandwich recipe doesn’t need complicated ingredients. With fresh hoagie rolls, deli roast beef from the deli counter, slices of provolone cheese, and crisp vegetables, you can make a great sandwich right at home without relying on fast food. Everything comes together quickly for a satisfying quick lunch.

This sandwich has been made using the same skills learned as a sandwich artist. The key to a healthy sandwich is ensuring proportions don’t get out of control. This roast beef sub is a great choice for an everyday satisfying sandwich.

If you love a good roast beef sandwich, try our hot roast beef sandwich recipe using leftover roast beef. 

Why You Will Love This Easy Sandwich Recipe

Balanced Flavors. The roast beef, onions, spinach, provolone cheese, and sweet onion vinaigrette create a perfect blend of savory, sweet, and tangy flavors.

Convenient and Portable. This sub is easy to pack and carry, making it a hassle-free lunch option.

Quick and Easy to Prepare. This roast beef sub is simple to assemble with readily available ingredients, saving time in the morning and making it ideal for busy schedules.

What Is a Submarine Sandwich?

A submarine sandwich, often called a sub, hoagie, or grinder, is a long sandwich served on a soft roll and filled with meats, cheeses, and vegetables. According to the history of the sandwich, the name “submarine” comes from the sandwich’s long shape.

Roast beef subs are a classic deli option known for their rich flavor and simple ingredients.

How to Make a Roast Beef Sub Sandwich

When making a sub sandwich, the first thing you need to do is cut the hoagie roll. Use a sharp knife or bread knife and place the roll on a cutting board so you can safely slice through the top bun and bottom half of the roll. There are a couple of simple tricks that make preparing the sandwich easier. Using a bread knife helps create a nice, even cut. The buns are longer and relatively soft inside, so you must be careful not to tear the bread while cutting. Instead, let the serrated edge do the work with a gentle sawing motion.

Gently place your free hand on top of the bun to steady it as you cut through the center. Years ago when I first worked at Mr. Sub, this was the standard way we cut the bread. Later, when I worked at Subway, they experimented with cutting a U-shaped notch out of the roll to create a trench for the ingredients. While it looked neat, it didn’t leave much of a top to the sandwich, so they eventually went back to cutting straight through the center.

Once the bun is ready, begin layering the ingredients. Start by placing the provolone cheese on the bottom half of the roll. If you are using round slices, cut them in half and lay them across the bread so they slightly overlap.

Next add the roast beef. The amount of meat is flexible. The recipe card lists a guideline, but you can easily increase or reduce the amount depending on who you are feeding and what you have on hand. At the restaurants we weighed every portion exactly, but at home it’s perfectly fine to adjust. Fold the roast beef slices as you place them so they create small air pockets. This gives the sandwich a fuller appearance and a nicer texture when you bite into it. Thin roast beef slices from the grocery store deli counter work perfectly and give you the same texture as a classic deli roast beef sandwich.

Now add the vegetables. Pile on the baby spinach and thinly sliced white onion rounds. You can add a little more spinach than most sandwich shops use if you like. It adds freshness and a nice bit of crunch to the sandwich.

Finally, drizzle the sweet onion vinaigrette lightly over the ingredients. Because sub rolls are soft inside, you don’t want to add too much dressing or the bread may become soggy. The dressing should add flavor and just a little moisture, not overwhelm the sandwich. If you prefer a stronger flavor, you could also spread a little Dijon mustard or horseradish mayo on the top bun before closing the sandwich.

Place the top bun over the fillings and cut the sandwich in half if desired. It can be wrapped and packed for work lunches or picnics. This sandwich is best made the day you plan to eat it, but if you are preparing it ahead of time, wait to add the sweet onion dressing until just before serving so the bread stays fresh.

Note: If you prefer a warm sandwich, place the assembled sub on a baking sheet and heat it in a 350-degree oven for a few minutes until the cheese becomes slightly melty.

Ingredients:

Sub Bun: Soft, fresh sub buns provide the perfect base, holding all the ingredients together and ensuring each bite is deliciously consistent.

Roast Beef: Tender, thinly sliced deli roast beef adds rich, savory flavor and a hearty, satisfying protein element to the sandwich.

Red Onion: Fresh, crisp onions add a sharp bite and crunch, balancing the richness of the roast beef with a touch of zing.

Provolone Cheese: Mild and creamy, provolone melts beautifully and pairs perfectly with roast beef.

Baby Spinach: Once it has been washed and dried, you can add more than you might see at a restaurant. Baby spinach adds freshness and extra nutrients while keeping the sandwich light and flavorful.

Sweet Onion Dressing: The tangy sweetness of the sweet onion dressing ties everything together, enhancing the flavors of the other ingredients and adding a delightful finish.

Substitutions and Add-Ins For This Easy Roast Beef Sub

Sub Bun: If you find it hard to locate good hoagie rolls in your local grocery store, replace them with whole wheat rolls, an onion roll, or even a loaf of French bread for a slightly different style of sandwich.

Roast Beef: Swap with sliced turkey or grilled chicken for a lighter, leaner protein option.

Red Onion: Use sweet onion for a milder, sweeter flavor, or try shallots for a more delicate taste.

Swiss Cheese: For a different flavor profile, replace it with cheddar or provolone cheese. If you prefer, you can even use a tasty American cheese on this sandwich. 

Baby Spinach: Substitute with arugula for a peppery kick or romaine lettuce for a crunchier texture. The restaurant chains generally use iceberg lettuce sliced very thin as it’s a more economical choice. 

Sweet Onion Dressing: Try balsamic vinaigrette or honey mustard for a sweet and tangy complement to the sandwich. If you prefer, a simple spread of Dijon mustard will also make a tasty sandwich. 

Other traditional toppings for sub sandwiches include green bell peppers, black olives, dill pickles, cucumber, tomato slices, and jalapenos. Don’t let that limit you when building a great sandwich. In fact, other great toppings for a roast beef sandwich may include bacon, caramelized onions, sauteed mushrooms, roasted red peppers, and sun-dried tomatoes. Sandwiches are the perfect canvas for many great combinations, which is one reason chains like Subway became so popular.

Can This Roast Beef Sub Be Served Hot?

While this recipe is designed as a cold roast beef sub sandwich, you can easily turn it into a hot roast beef sandwich if you prefer a warm meal. Simply heat the roast beef slices in a large skillet with a little olive oil over medium-high heat until warmed through. Some people also like to dip the sandwich in au jus made from beef broth for an extra layer of flavor.

Expert Tips, Serving, And Storing Suggestions For These Roast Beef Subs:

Tip #1: Use a Sharp Bread Knife: A sharp knife makes it easier to slice through the hoagie roll without tearing the bread.

Tip #2: Layer Strategically: Place the heavier ingredients, like roast beef and cheese, at the bottom and the lighter, more delicate items, like spinach and onions, on top. This layering technique ensures the sandwich holds together well and each bite is balanced. 

Tip #3: Use Fresh, High-Quality Ingredients: Fresh ingredients significantly affect flavor and texture. Opt for fresh deli roast beef, crisp vegetables, and quality cheeses and dressings. 

This roast beef sandwich recipe is perfect for lunch or a light dinner, whether at home, at work, or enjoying a picnic. Serve the cold sandwich with potato chips, a pickle spear, or a fresh salad for a complete meal. For the best flavor, serve the sandwich freshly made the same day. 

To keep uneaten portions of your roast beef sandwich fresh:

1. Wrap the sub sandwich tightly in plastic wrap and store it in the fridge.
2. Consume within 24 hours for the best quality.
3. If you anticipate storing it for longer, keep the sweet onion dressing separate and add it just before eating to maintain optimal texture and flavor.

Did you make this delicious roast beef sub? We’d love to hear about your experience! Leave us a rating and comment below to let us know how it turned out. Your feedback helps us improve and inspires others to try this tasty recipe, too. Thank you for sharing your thoughts!