Drain cherries, reserving juice. Place sugar and cornstarch in saucepan and stir to mix. Pour one cup of juice in saucepan and turn burner to medium. Cook and stir until mixture thickens, about 5-8 minutes. Add cherries and stir to coat. Add food coloring if desired.
Cut pastry into circles or triangles to fit individual tart or muffin pans.
Spray pan with cooking spray and gently insert dough pieces to form crusts.
Place 1/2 tsp of cream cheese in the bottom of tarts if desired.
Fill tarts with cherry filling and top with a dough shapes cut from remained pie dough round, if desired.
Bake at 400 20 minutes or until golden and done, watching carefully.