PLACE THE FLOUR, SUGAR, SALT AND COLD BUTTER INTO A BOWL AND QUICKLY BLEND WITH YOUR FINGERS TO BREAK THE BUTTER INTO SMALL PEA-SIZE PIECES (THIS CAN BE DONE IN A FOOD PROCESSOR AS WELL). ADD IN THE BEATEN EGG AND SOME OF THE COLD WATER. BLEND UNTIL YOU HAVE A DOUGH THAT JUST HOLDS TOGETHER WHEN SQUEEZED.ADD A BIT MORE WATER IF NEEDED
WRAP THE DOUGH IN PLASTIC WRAP FORMING A FLAT DISC. CHILL FOR AT LEAST 25 MINUTES.
WHILE THE DOUGH IS CHILLING, COMBINE THE BLUEBERRIES, ZEST, JUICE, SUGAR, CORNSTARCH AND CINNAMON WITH A SPLASH OF WATER
TOSS AND THEN POUR INTO A HIGH SIDED PAN/SKILLET
COOK OVER MEDIUM LOW HEAT FOR 8-10 MINUTES STIRRING OCCASIONALLY AND PRESSING ON THE BERRIES UNTIL THEY HAVE BROKEN DOWN A LITTLE AND THE JUICES HAVE THICKENED. SET ASIDE TO COOL
preheat oven to 375F
ROLL THE CHILLED DOUGH OUT INTO A RECTANGLE ABOUT ¼ INCH THICK. CUT INTO EIGHT EQUAL SMALLER RECTANGLES
PLACE A HEAPED TABLESPOON OF THE BLUEBERRY FILLING ONTO ONE END OF THE RECTANGLE. FOLD THE TOP EDGE OVER THE FILLING AND PRESS INTO THE BOTTOM EDGE. GENTLY PRESS THE SIDES CLOSED. THE USE YOUR FINGERS OR A FORK TO FURTHER PINCH THE EDGES TOGETHER UNTIL SEALED
BRUSH EACH PIE WITH EGG WASH AND SPRINKLE WITH SUGAR. CUT A SMALL “X” IN THE TOP TO VENT.