Open the can of tomatoes, pour off the juice, and discard. With your hands, squeeze the whole tomatoes to a pulp, adding pulp to a bowl as you squeeze. Set aside.
Heat olive oil in a heavy saucepan over high heat. Add garlic and cook until golden and fragrant; be careful not to burn the garlic. Add tomato pulp, stir to combine, and reduce the heat to a simmer. Simmer for about 5 minutes. Season, to taste, with salt and pepper. Serve as a dipping sauce for the bocconcini.