Heat oven to 375°F. Lightly spray 12 mini muffin cups with cooking spray.
In 2-quart saucepan, mix all filling ingredients. Cook over medium heat 10 minutes, stirring occasionally, until sugar is dissolved and berries are softened. Remove from heat; with back of wooden spoon, gently crush berries. Cool.
Meanwhile, remove 1 pie crust from pouch (keep other crust refrigerated); unroll crust on floured surface. With 2 3/4-inch round cookie cutter, cut out 12 rounds. Gently push 1 pastry round into each muffin cup. Divide filling between pastry-lined cups, about 1 teaspoon in each.
Unroll second pie crust; with 2-inch round cookie cutter, cut out 12 rounds. With 1-inch star-shaped cookie cutter, cut out stars from 4 circles. Place 4 stars on 4 of the rounds; place star-topped rounds on 4 pies and gently seal edges. Place remaining 4 stars on center of 4 more pies. Cut remaining 4 rounds into tiny strips; create lattice design on remaining 4 pies. In small bowl, beat egg and water. Brush over tops of pies. Sprinkle with sanding or sparkling sugar.
Bake 12 to 15 minutes or until lightly browned. Cool slightly before serving.