Line a 3 quart casserole with one of the pie crusts; line crust up sides as well as on bottom of dish. Pour washed, drained berries on top. Mix sugars, flour, salt, cinnamon, egg yolks, and butter; mixture should be moist and crumbly.
Pour on top of fruit evenly. Cut remaining pie crust into strips and lay diagonally on top of cobbler. May sprinkle additional sugar lightly on top before baking, if desired. Bake in a 425 degree oven 15 minutes, reduce heat to 350 degrees and bake 45 minutes to an hour, until done.