This recipe grew out of a rainy Saturday when I wanted everything comforting about a Philly cheese steak but in a bowl. I first made this during a week when takeout felt like too much effort and I had leftover roast beef from a deli run. The result captured all the satisfying textures of the sandwich: soft, peppery vegetables, savory shredded beef, and a velvety, slightly tangy broth that hugs the bread when you dunk it. It became a fast favorite for chilly evenings and casual dinners when everyone needed something warm and familiar.

What makes this preparation special is the balance between richness and clarity. The butter and half and half create a silky body, while the beef broth and Worcestershire sauce cut through with umami. The shredded provolone folded in at the end gives that classic cheesy stretch you expect from the sandwich — only now it dissolves into the liquid for spoonfuls that feel indulgent but not overly heavy. Every time I make it, family members comment on the way the peppers keep a little bite and the mushrooms add earthy depth.

Ingredients

• Butter (1/4 cup): Use unsalted butter so you can control seasoning; it provides the fat that sautés the vegetables and helps build the roux when mixed with flour. European-style butter will add a slightly richer finish.
• Yellow onion (1 cup, diced): Choose a firm, sweet yellow onion for depth and a touch of sweetness when caramelized; dice small so it softens quickly and integrates into the broth.
• Green bell pepper (1 cup, diced): Adds freshness and a mild grassy note; remove seeds and membranes for a sweeter bite. You can substitute a red pepper for more sweetness.
• White mushrooms (6 oz, sliced): Button or cremini both work; mushrooms add umami and texture. Wipe them clean and slice evenly so they cook at the same rate as the onion and pepper.
• Roast beef (8 oz, chopped): Leftover deli roast beef or cooked roast, chopped into bite-size pieces. Thinly sliced or shredded beef will integrate best and heat through quickly.
• Garlic (1 tablespoon, minced): Fresh garlic adds aromatic lift; add after the beef to avoid burning and becoming bitter.
• All-purpose flour (1/4 cup): Used to create a light roux that thickens the broth when combined with butter; cook briefly to remove the raw flour taste.
• Beef broth (4 cups): Use low-sodium broth if possible to control salt. A rich, store-bought or homemade broth will make the base more savory.
• Half and half (3 cups): Provides creaminess without being as heavy as heavy cream. Whole milk will thin the soup; heavy cream will make it thicker and richer.
• Worcestershire sauce (1 tablespoon): A small amount boosts meaty umami notes and brings the flavor profile closer to the sandwich.
• Salt and pepper (1 teaspoon each): Adjust to taste; start with the amounts listed and finish seasoning after the cheese is incorporated.
• Cornstarch slurry (3 tablespoons cornstarch mixed with 1/4 cup water): Use this to thicken without cloudiness. Mix until smooth before adding to the hot liquid.
• Shredded provolone (for topping): Freshly shredded provolone melts more smoothly than pre-shredded; reserve a generous handful per bowl for the best melt and flavor.

Instructions

Heat the fat:Melt the 1/4 cup butter in a large, heavy-bottomed pot over medium heat. Watch the butter so it foams but does not brown; this ensures the vegetables will cook evenly without burning.Sauté aromatics and vegetables:Add the diced yellow onion, diced green bell pepper, and sliced mushrooms. Sauté for 6 to 8 minutes until the onions are translucent and the peppers soften; stir frequently and look for glossy vegetables with lightly browned edges.Add the beef and garlic:Stir in the chopped roast beef and mix to warm it through for about 2 minutes. Push the mixture to one side, add the minced garlic, and cook for 30 to 45 seconds until fragrant. Avoid letting garlic brown.Make the roux:Sprinkle the 1/4 cup flour evenly over the mixture and stir continuously for about 3 minutes. The flour should absorb the butter and take on a slightly toasted aroma — this removes any raw flour taste and thickens the soup gently.Add liquids:Gradually pour in 4 cups beef broth while stirring or whisking to avoid lumps. Bring the pot to a gentle boil, then reduce to a simmer and stir in 3 cups half and half. Heat through, maintaining a gentle simmer so the mixture does not fat-separate.Season and simmer:Stir in 1 tablespoon Worcestershire sauce, 1 teaspoon salt, and 1 teaspoon pepper. Bring to a low boil, then reduce heat and simmer for 8 to 10 minutes to let flavors meld; skim any foam or excess fat if needed.Thicken with slurry:Whisk the cornstarch and 1/4 cup water together until smooth. Slowly pour the slurry into the boiling soup while stirring; allow the soup to return to a boil for about 1 minute so the starch reaches full thickening power.Finish with cheese:Reduce heat to low and stir in shredded provolone a handful at a time until fully melted and incorporated. Taste and adjust seasoning. Serve hot with extra cheese on top and fresh parsley if desired.

Storage Tips

To keep this preparation at peak quality, cool to room temperature within two hours and transfer to airtight containers. Refrigerate for up to three days. For longer storage, portion into freezer-safe containers and freeze for up to three months. When reheating from frozen, thaw overnight in the refrigerator, then warm gently on the stovetop over low heat, adding a few tablespoons of half and half or water to bring back a smooth mouthfeel. Avoid high, fast heat to prevent the dairy from separating; a slow, steady warm-up preserves texture.

Ingredient Substitutions

If you need to adapt, use one cup whole milk plus 1/2 cup heavy cream instead of 3 cups half and half for a richer finish, or swap in all-purpose gluten-free flour and a dairy-free creamer to make it gluten-free and dairy-free respectively. For a leaner protein, substitute thinly sliced roast turkey or leftover steak. If you want a sharper cheese flavor, mix provolone with smoked gouda or a touch of sharp cheddar; melt slowly and taste as you go to keep balance.

Serving Suggestions

Serve in wide bowls with a sprinkle of shredded provolone and chopped fresh parsley. Offer crusty Italian rolls or toasted sourdough for dunking; the slightly salty bread complements the cheesy broth. For a lighter meal, serve with a crisp green salad dressed in a lemon vinaigrette to cut through the richness. Garnish with a few quick-pickled pepper slices for brightness, or add a drizzle of extra virgin olive oil and cracked black pepper for finishing flavor and sheen.

Cultural Background

This interpretation transforms the classic Philadelphia sandwich into a hearty bowl while maintaining its core identity: sautéed onions and peppers, thinly sliced beef, and melted cheese. The sandwich itself has roots in early 20th-century Philadelphia, where vendors began layering cooked beef and onions, later adding cheese. Turning it into a soup is a contemporary comfort-food twist that highlights regional flavors while offering a more spoonable experience that many home cooks enjoy in colder months.

Seasonal Adaptations

In winter, use roasted red peppers and add a teaspoon of smoked paprika for a cozy smoky note. In spring, brighten with a handful of chopped fresh basil and finish with lemon zest to lift the heavier elements. Summer calls for lighter dairy like a single cup of half and half plus two cups whole milk, and use fresh, ripe peppers. For holiday occasions, bulk it up with diced roasted potatoes or serve in hollowed-out bread bowls for a festive presentation.

Meal Prep Tips

To streamline weekday dinners, prepare the vegetable and beef base up to the simmer stage, cool, and refrigerate for up to 48 hours. When ready to serve, reheat, whisk in the cornstarch slurry to thicken, and finish with the cheese. Portion into microwave-safe containers for quick lunches — reheat on medium power and stir halfway through to ensure even heating. Use stackable, BPA-free containers to save space in the freezer and label with dates.

Every time I ladle this into bowls I’m reminded of the first time I turned sandwiches into soup: it felt like a small creative risk that paid off. I hope you enjoy making it your own and sharing it at your table.