First prepare the sauce by heating the olive oil in a medium saucepan over medium heat. Add the onion, garlic and oregano and cook for 3-4 minutes until softened, stirring frequently.
Add the tomato paste and cook for 1 minute, stirring constantly
Add the diced tomatoes, reduce the heat to medium-low and simmer for 8-10 minutes, until thickened, stirring occasionally.
Season with salt and pepper, if desired. Remove from the heat and stir through the fresh basil and parsley and adjust the seasoning if needed.
Transfer the sauce to a high-powered blender (or use a stick blender) and blend until the desired consistency is reached. For a chunkier sauce, puree half of the sauce mixture and mix it back through the sauce. For a smooth sauce, puree it all, set aside
Cook the spaghetti according to package instructions
To prepare the Quorn mince, heat the oil in a saucepan and fry the onion, carrot, celery and garlic gently for 5 minutes. Add the mushrooms, herbs and fry for a further 2-3 minutes
Add the sauce to the Quorn, stir to combine and fry for a further 5 minutes
Serve on a bed of the cooked spaghetti