Heat oven to 450°F. Line cookie sheet with parchment paper or nonstick foil.
Unroll pie crust onto cutting board. Using mini (1-inch) star-shaped cookie cutters, cut out stars, and place on cookie sheet. Gather and reroll dough to maximize the number of stars you get.
In small bowl, beat egg whites with whisk until loose and liquidly. Divide evenly among three bowls. In one bowl, beat in red food color. In second bowl, beat in blue food color. Leave third bowl uncolored. Using pastry brush, brush stars with egg whites, brushing one-third of the stars red, one-third blue and one-third uncolored. Sprinkle generously with salt.
Bake 6 to 7 minutes or until lightly browned. Remove from cookie sheet to cooling rack; cool.
Serve immediately, or store tightly covered up to 5 days.