This Philly Cheese Steak Soup started as a weeknight experiment the first winter I moved into my own kitchen. I was craving the savory hit of a classic sandwich but wanted something warm, spoonable, and easy to share. The moment the soup simmered and the aroma of onions, peppers, and beef filled the house, I knew I had a keeper. What makes this version special is the balance of textures: tender chopped roast beef folded into a velvety broth thickened with a flour roux and finished with half and half, then crowned with melted provolone for a gooey contrast.

I first discovered this combination when I had leftover deli roast beef and a carton of half and half to finish. Rather than reheating slices on bread, I transformed them into a creamy bowl and the result turned every skeptic at my table into a fan. The soup carries all the familiar flavors of the sandwich but feels lighter and more comforting because each spoonful includes broth, vegetables, and cheese. Over time I refined the sauté technique for the vegetables and learned to coax maximum melt from the cheese without breaking the cream. This recipe is now my go to for busy evenings and casual gatherings when I want something that tastes indulgent without being complicated.

Ingredients

• Butter: 1/4 cup. Use salted European style butter if you prefer a slightly richer mouthfeel; it helps brown the vegetables and provides the base fat for the roux.
• Yellow onion: 1 cup diced. Look for firm, heavy bulbs with dry skins; they add natural sweetness once sweated and create a savory backbone.
• Green bell peppers: 1 cup diced. Pick crisp, bright peppers for crunch and a mild vegetal note reminiscent of the sandwich.
• White mushrooms: 6 ounces sliced. Cremini or white button both work; mushrooms deepen the umami and add a meaty texture that complements the roast beef.
• Roast beef: 8 ounces chopped. Thinly sliced deli roast beef or leftover roast chopped into bite sized pieces provides the signature flavor; use good quality roast for best taste.
• Garlic: 1 tablespoon minced. Fresh garlic added late gives aroma without bitterness; use peeled cloves minced finely.
• All purpose flour: 1/4 cup. This forms the roux with butter to thicken the broth smoothly; whisk well to avoid lumps.
• Beef broth: 4 cups. Low sodium is recommended so you control seasoning; a rich, well made stock improves overall depth of flavor.
• Half and half: 3 cups. This creates the creamy body without being as heavy as heavy cream; shake or stir before measuring to incorporate.
• Worcestershire sauce: 1 tablespoon. Adds savory complexity and a touch of tang that echoes the sandwich experience.
• Salt and pepper: 1 teaspoon each, then adjust to taste. Start conservative if your broth or roast beef is already salted.
• Cornstarch slurry: 3 tablespoons cornstarch mixed with 1/4 cup water. Used to finish and tighten the consistency if needed for service.
• Shredded provolone: For topping. Use a high quality provolone that melts smoothly; shredded cheese disperses quickly and offers the classic tang and pull.

Instructions

Melt the butter: Place a large heavy bottom pot over medium heat and add 1/4 cup butter. Let it foam and subside but avoid browning; the goal is a glossy surface to sauté vegetables. Medium heat prevents the butter solids from burning while giving time for the aromatics to soften. Sauté the vegetables: Add the diced yellow onion, diced green bell peppers, and sliced mushrooms. Cook, stirring occasionally, until the onions become translucent and the peppers soften, about 6 to 8 minutes. Look for the mushrooms to give up their moisture and begin to brown at the edges which concentrates flavor. Add the roast beef: Stir in the chopped roast beef and distribute it evenly through the vegetables. If using cold roast beef straight from the refrigerator, allow an extra minute to warm through. The goal is not to crisp the beef but to integrate its flavor into the base. Garlic and flour: Stir in 1 tablespoon minced garlic and cook until fragrant, about 30 seconds. Sprinkle 1/4 cup all purpose flour over the mixture and stir constantly for about 3 minutes to cook off raw flour taste and develop a light nutty aroma. This forms a roux that will thicken the broth. Add broth and dairy: Gradually pour in 4 cups beef broth while stirring to avoid lumps. Once the broth is incorporated, add 3 cups half and half, stirring until smooth. Increase heat to bring the mixture to a gentle boil, then reduce to a simmer. The roux will thicken as it heats; simmer for 10 minutes to allow flavors to marry. Season and finish: Stir in 1 tablespoon Worcestershire sauce, 1 teaspoon salt, and 1 teaspoon pepper. If the soup seems thinner than you prefer, whisk the cornstarch slurry made from 3 tablespoons cornstarch mixed with 1/4 cup water and add gradually while the soup is boiling to reach the desired consistency. Remove from heat and stir in shredded provolone until melted and silky. Serve: Ladle into warm bowls and top with additional shredded provolone and chopped fresh parsley for color. Serve with crusty bread or hoagie rolls for dipping.

Storage Tips

Cool the soup to room temperature before storing. Transfer to airtight containers and refrigerate for up to three days. For freezing, portion into freezer safe containers leaving an inch of headspace and freeze for up to three months. When reheating from frozen, thaw overnight in the refrigerator and rewarm gently on low heat, whisking occasionally. If the texture separates, whisk in a splash of fresh half and half or a tablespoon of butter to re-emulsify and return creaminess.

Ingredient Substitutions

If you do not have roast beef, thinly sliced steak such as ribeye or sirloin can be quickly seared and added. For a gluten free version, substitute a 1 to 1 gluten free flour blend and use cornstarch slurry as the primary thickener. To make dairy free, use an unsweetened oat beverage or cashew cream and replace butter with olive oil. Note that changing the dairy will alter both richness and mouthfeel so adjust seasoning and thickening accordingly.

Serving Suggestions

Serve bowls with extra shredded provolone and chopped parsley for freshness. Offer crusty bread or toasted hoagie rolls for dipping and a simple green salad to cut the richness. For a heartier meal, serve with roasted potatoes or a plate of roasted vegetables. Garnish with thinly sliced raw green onions for a sharp counterpoint.

Cultural Background

The classic sandwich that inspired this soup has roots in Philadelphia and is known for its thinly sliced beef, sautéed peppers and onions, and melting cheese on a roll. This potable adaptation borrows those elements and reframes them into a bowlable comfort food, reflecting how regional favorites evolve into new forms in home kitchens across the country.

Seasonal Adaptations

In colder months, increase mushrooms and add a splash of red wine to deepen richness. In spring or summer, lighten the soup by using whole milk and incorporating diced tomatoes or fresh herbs like basil. For holiday gatherings, double the batch and keep warm in slow cookers for easy serving.

Meal Prep Tips

Make a double batch and portion into single serving containers for quick lunches. Keep shredded provolone separate and add just before reheating to preserve meltability. Label containers with the reheating method and date to ensure the best texture when serving later in the week.

There is something deeply satisfying about turning familiar sandwich flavors into a spoonable comfort dish. Share bowls with friends, tuck leftovers into lunches, and make small adjustments to match your pantry and preferences. Enjoy the cozy, melty comfort of this version of Philly Cheese Steak Soup and make it your own.