Preheat oven to 325°F (160°C).

Lightly grease two 12-hole shallow patty pans.

Cut rounds from the thawed pie dough using a 3-inch cutter.

Ease the dough rounds into the prepared patty pans.

In a small bowl, beat eggs and sugar using an electric mixer until creamy.

Beat in milk and food coloring (if using) until well combined.

Pour the custard filling into the prepared pie crusts.

Bake for 40-45 minutes, or until the dough is golden brown and the filling is just set.

Cool the tarts in the pan for 5 minutes.

Transfer the tarts to a wire rack to cool completely.

Serve warm or cold.