Crust: Put the flour, salt, sugar into the bowl of a food processor. Pulse a few times. Add in 1 tsp. vanilla and while you pulse as you go, add the chunks of butter one at a time. Pulse until you have small pea size pieces. Start adding the 7 tablespoons of water as you pulse. When this starts to come together, turn out onto pastry cloth or cutting board and form into a disk. Wrap in plastic wrap and refrigerate for 15 minutes. Flour your board or cloth a little (don’t use too much flour) and also a little on your rolling pin. Roll the pastry to a 14″ circle. Move this onto your large cookie sheet. It can overlap the edges a little because you are going to be folding in the edge over the fruit. Topping: Peel, pit and slice the peaches and nectarines. Put the peaches, nectarines, blackberries, and raspberries in a bowl. Toss these with the sugar and flour until coated. Spread the cherry jam on the center of the crust, leaving about 1 1/2-2″ not covered with the jam around the outside edges. Arrange your fruit in the center coming to withing the same 1 1/2-2″ of outside edge. Now start folding in the crust over he fruit, pleating when necessary, all the way around the tart. Beat the egg with the water. Brush this mixture over the turned up crust edge and sprinkle with sugar. Bake in 350° for 30-40 minutes or until nicely browned.