1. Butter a 9-inch tart pan with a removable bottom. In a food processor, pulse the flour with a pinch of salt and the butter until the mixture resembles coarse meal. Add the cream and pulse until the dough nearly comes together. Turn the dough out onto a floured work surface and knead a few times. Cover and refrigerate for at least 30 minutes or overnight.
2. Preheat the oven to 325°. Roll out the dough to a 14-inch round. Press the round into the tart pan; trim off any excess. Mound the tomatoes in the shell. Bake for about 1 hour and 40 minutes, until the dough is evenly browned. Let cool. Season with salt, garnish with the basil and serve.