Gather and prep all ingredients.

Melt butter in a medium-sized pot over medium heat. Once hot, add the onions and sauté until tender but not browned, about 3-4 minutes. Add in the peppers, mushrooms and sprinkle with salt and pepper. Cook another 3-4 minutes, stirring occasionally, until tender.

Add in the roast beef, then stir through to combine. Add the broth and bring to a simmer. Once simmering, reduce heat slightly and cook for 10 minutes.

Remove about 1/4 of the hot broth from the pot and optionally add to a blender with the cream cheese and heavy cream. Blend until cream cheese is thoroughly incorporated. If not using a blender, whisk the cream cheese and cream into the soup until combined with the broth.

Re-pour the mixture from the blender into the pot, then stir to combine.

Set the broiler to high. Pour the soup into ramekins or oven-safe bowls, then top each with a slice of provolone. Set on a baking sheet, and broil for 2 to 4 minutes, or until the cheese is melted and bubbling.

Serve and enjoy!