Heat a frying pan and pour in some vegetable oil. Fry the beef over high heat for 1 minute on each side to give it a golden crust. You don’t need to fry it for long, as the roast beef will be finished in the oven.
Place the roast beef in a baking dish, season with salt and pepper to taste. Place the roast beef in the oven to bake for 20 minutes.
Meanwhile, slice the red onion into thin rings.
Finely chop the chili pepper.
Chop the garlic.
In a bowl, combine olive oil, soy sauce, garlic and chili pepper. Add Provencal herbs, crushed allspice, salt and black pepper to taste. Stir.
Add red onion rings to the marinade. Mix gently.
Place the finished roast beef in the onion marinade. Cover the roast beef with cling film or a lid and put it in the refrigerator to marinate for 4 hours.
Slice the marinated roast beef thinly, place on a plate and garnish with pickled red onion. Serve the roast beef with a sauce such as creamy garlic or tartar. Enjoy.