In a saucepan over medium heat, combine blueberries and sugar. Simmer for 5 minutes until sugar dissolved. Add lemon zest, lemon juice, and honey. Simmer for another 5 minutes. Add cornstarch dissolved in water. Simmer until thickened. Turn off the heat. Add cinnamon powder, nutmeg, and vanilla. Mix until well blended. Set aside and let it cool.

Preheat oven to 400F. Line a baking sheet with parchment paper. Unroll the thawed puff pastry on a clean flat surface or large cutting board. Use a pastry cutter or paring knife to cut each puff pastry into 9 small squares.

In a small bowl beat egg and water. Lightly brush the half triangle edges of puff pastry with egg wash and spoon 3/4 tablespoon of blueberry filling on the center of puff pastry.

Fold into a triangle, use a fork and press the edges to seal. Brush the top of each turnover with egg wash. Sprinkle with turbinado sugar.

Use kitchen scissor or paring knife, slit or snip the top of each turnover. Bake for 10 to 15 minutes until golden brown. Remove from the oven and let it cool.