Pre-heat the oven to 400 levels F having a baking sheet around the middle rack. Inside a large bowl, chuck the ball blackberries, sugar, corn starch, fresh lemon juice and lemon zest. Let stand, mixing and coarsely mashing from time to time, twenty minutes.
Fit one round of dough right into a 9-inch cake plate. Trim the perimeters, departing singleOr2-inch overhang. Refrigerate when you continue. Cut the rest of the bit of dough into roughly eleven 11/4-inch-wide strips.
Spoon the rim mixture in to the cake spend. Us dot the very best using the butter. Arrange the dough strips inside a lattice pattern on the top from the filling and trim the strips on the brink from the pan roll-up and crimp the advantage. Gently beat the egg with 1 tablespoon water and brush on top and fringe of the cake.
Look for a lattice how-to at HYPERLINK " " or simply lay 1 / 2 of the dough strips evenly around the cake and arrange the rest of the strips diagonally across them.