In a large heavy bottomed pan, heat the olive oil over medium heat. Add the chopped onion and cook until soft and translucent, about 5 minutes. Add the minced garlic and cook for an additional minute.

Add the sliced mushrooms to the pan and cook, stirring occasionally, until they release their moisture and begin to brown, about 8-10 minutes.

Stir in the smoked paprika, Italian seasoning, salt, and pepper. Cook for 1-2 minutes until fragrant.

Sprinkle the flour over the mushroom mixture and stir well to combine. Cook for 1-2 minutes to remove the raw flour taste. Gradually add the vegetable broth, stirring constantly to prevent lumps. Bring to a simmer and cook until the sauce thickens, about 3 minutes.

Stir in the Dijon mustard and Worcestershire sauce. Reduce the heat to low and add the sour cream. Stir until well combined and heated through, but do not let it boil.

Stir in the lemon juice and chopped parsley. Taste and adjust the seasoning with more salt and pepper if needed.

Serve the stroganoff over rice, noodles or mashed potatoes. Garnish with additional parsley if desired.