8 large plum tomatoes, sliced crosswise 1/3 inch thick
Salt and freshly ground pepper
Preheat the oven to 275°. In a mini food processor, process the basil, olive oil, olives and rosemary to a paste.
Arrange the tomato slices on a large, rimmed baking sheet and season with salt and pepper. Spread about 1 teaspoon of the tapenade over each tomato slice. Bake for 1 1/2 hours, until the tomatoes are very tender. Serve hot or warm.