Creamy sauces do not freeze well, but tomato-based spaghetti or marinara sauces do. When you make a large batch, store the extra in the freezer to pull out on an evening when you don't want to cook. You'll have the goodness of homemade without all the effort.
Step 2: Cool it.
Allow the sauce to cool completely, either to room temperature or in the refrigerator overnight.
Step 3: Package it.
Place the sauce in storage containers. Choose freezer bags with zip tops and lay them flat in the freezer. You may also put the sauce into jars or other freezer-safe sealable glass containers. Leave a little space at the top -- about 1/2 inch -- for the sauce to expand as it freezes.
Each storage container should contain only as much as you plan to use for one meal for yourself or your family.
Step 4: Label.
Label the package with the name of the sauce and the date. The sauce should last about three months in the freezer.
To thaw, simply place the frozen sauce in a saucepan; cover, and slowly warm it over low heat. Check often, and stir to speed up the defrosting and to ensure the bottom doesn't burn. Bring it up to a simmer and add any ingredients that don't do well in the freezer -- such as a splash of cream or cheese.
Alternatively, thaw the sauce in its container in the refrigerator overnight.
If you freeze pesto, don't cook it to thaw it or the basil and garlic flavors will turn slightly bitter. Simply thaw it in the refrigerator overnight. Because it only has a small amount of cheese, you can freeze pesto with the cheese added or wait to add it until after it's thawed.