Joan Nathan'S Red, White, And Blue Fruit Crisp

First, make the crust by using a food processor fitted with a metal blade. Pulse the flour, salt, and 1/2 cup sugar together.
Divide the butter or coconut oil into smaller amounts, add gradually to the bowl, and process until crumbly. Add the egg yolks and process until a ball is formed, adding more flour if necessary.
(To make the dough by hand, use your fingers or a pastry blender to work the butter into the flour, salt, and 1/2 cup sugar until the mixture resembles coarse breadcrumbs. Add the egg yolks and work the dough into a ball.)
Flatten the dough with your hands or a rolling pin to about a half-inch thickness, wrap in plastic wrap, and refrigerate for at least a half hour.
When you're ready to make the crisp, preheat oven to 450.
Put the fruit in a 9-by-13-inch Pyrex pan. Sprinkle lemon zest, the preserved ginger, and the remaining 1/2 cup sugar over all; mix together with the fruit, using your hands.
Remove the crust from the refrigerator, pinch off nickel-sized bits of dough, and sprinkle over the top. You want it to be rustic.
Bake for about 30 minutes or until the crust is golden brown and the fruit juicy. Remove from the oven and set on a rack to cool. Serve warm or at room temperature, topped with generous scoops of vanilla ice cream.