Defrosting a pasta dish properly is essential to keeping the texture and flavor intact, especially if it contains dairy products. Moderate the duration and temperature with the volume of food so that the entire portion thaws thoroughly without degrading the ingredients.
The Refrigerator Method
A gradual change in temperature is less detrimental to the texture and flavor of the food than fast reheating. This method not only preserves the quality of the food, it also protects against contamination and spoilage.
Remove the lid or foil that covered the dish in the freezer. The cover may have frozen condensation, which, when melted, forms pools of water on top of the pasta. Cover the pasta with a fresh lid or new sheet of aluminum foil.
Place the pasta in the refrigerator to thaw slowly overnight. Most dishes only need one day, but dense portions may require extra time. Allow two days to thaw a large or deep dish.
Insert a toothpick or sharp knife into the center of the dish to determine if the food is thoroughly defrosted.
The Cold-Water Method
The cold water method raises the temperature of the food faster than the refrigerator method, but it should still retain the quality of the food.
Replace the lid or foil that covered the dish in the freezer to prevent condensation from pooling on top of the pasta as it thaws. Seal the top edge well to prevent water from seeping into the container.
Fill a dish larger than the container of frozen pasta with cool water.
Dip the container of pasta into the cool water. The water level should be roughly as high as the pasta is in the container but not high enough to leak into the food.
Leave the container sitting in the water. Change the water periodically, about once an hour, until the pasta is room temperature.
The Oven Method
It is safe to transfer most prepared pasta dishes such as lasagna and macaroni and cheese directly from the freezer to an oven at 400 degrees Fahrenheit, as long as they're in oven-safe pans.
Bake frozen pasta at 400 degrees Fahrenheit for 1 hour per pint of food. Keep the pasta covered with foil as it bakes to prevent the top from scorching before the middle cooks through.