Prepare spinach according to package directions. Drain in colander and press out excess water.

In a medium bowl, combine egg, cheese, onion, garlic and salt. Stir in spinach.

Place one of the pastry sheets on a large baking sheet. Place half of the spinach filling on the pastry and fold diagonally. Crimp edges with a fork. Repeat with the second pastry sheet.

Bake at 400°F for 20 minutes, or until golden brown.

Cut each turnover into 3 pieces and serve.