Place the dried wild mushrooms in a bowl and cover with warm water. Leave to soak for approximately 30 minutes, or according to the package instructions, until softened. Drain the mushrooms through a fine sieve, reserving the soaking liquid. If the liquid contains grit, strain it through a coffee filter or fine cloth.
Season the beef slices lightly with salt and freshly ground black pepper. Dust both sides with the flour, shaking off any excess.
Heat the olive oil in a large, heavy-bottomed casserole over medium-high heat. Working in batches, briefly brown the beef slices on both sides. They should develop a little color but do not need to cook through. Transfer to a plate and set aside.
Reduce the heat to medium. Add the chopped onions to the same casserole and cook for approximately 8–10 minutes, stirring occasionally, until softened and beginning to turn golden.
Add the chopped garlic and cook for another minute.
Add the sliced fresh mushrooms and cook for approximately 5 minutes, stirring occasionally, until they begin to soften and release their moisture.
Stir in the grated tomato and tomato paste. Cook for another 3–4 minutes, allowing the tomato mixture to reduce slightly.
Pour in the dry white wine and stir well, scraping up the browned bits from the bottom of the casserole. Allow the wine to simmer for approximately 2–3 minutes.
Return the beef slices to the casserole, together with any juices from the plate. Add the soaked wild mushrooms, beef stock and black olives.
Add some of the reserved mushroom soaking liquid for extra flavor, making sure any sediment has been removed. Use only as much as needed to create a generous sauce without completely drowning the meat.
Bring everything to a gentle simmer. Cover with a lid and cook over low heat for approximately 1½ hours, or until the beef is tender. Stir occasionally and make sure the sauce does not dry out.
If the sauce is too thin toward the end of cooking, remove the lid and simmer for another 5–10 minutes to reduce it. If it becomes too thick, add a little water or beef stock.
Taste and adjust the seasoning with salt and freshly ground black pepper. Remember that the olives and stock may already contain salt.
Sprinkle with finely chopped fresh parsley and serve hot with saffron rice, turmeric rice or crusty bread.