Preheat the oven to 350º
In a large gratin dish or pan, cover the bottom with olive oil. Add one layer of the onion slices. In top of that add the beef cubes, making sure that they are all the same size. Salt and pepper the meat. Another layer of potatoes and cover it all with the bacon. Add the can of tomatoes and the basil leaves. Lightly salt and put in the oven for 1 ½ hour.
Make sure that during cooking the juices are not drying up to much. If it becomes dry add couple of tablespoons of water to it, or wine.
Serve in the same dish.