Heat oil in large skillet over medium heat. Add onion and cook until tender.
Add turkey; cook until turkey is no longer pink, stirring occasionally.
Stir in garlic, oregano, chili powder and salt; set aside.
Heat oven to 375 degrees F. Lightly grease baking sheets.
Prepare Egg Yolk Paint; set aside.
On lightly floured surface, roll 1 pie crust to 14-inch diameter. Using
3-inch Halloween cookie cutters, cut out pairs of desired shapes.
Repeat with second pie crust, rerolling dough if necessary.
Place 1/2 of shapes on prepared baking sheets. Brush edges with egg white.
Spoon about 1 tablespoon taco mixture onto each shape. Sprinkle with 1 teaspoon
tomato and 1 teaspoon cheese. Top with remaining matching shapes; press edges
to seal. Decorate with Egg Yolk Paint.
Bake for 10 to 12 minutes or until golden brown.
Egg Yolk Paint: Place 1 egg yolk in each of 4 small bowls. Add 1 teaspoon
water and a few drops different food coloring to each; beat lightly.