Refrigerating Egg Yolks
Refrigerate unbroken raw egg yolks, covered with with water, for up to 2 days in an airtight container. If you can't use the yolks in 2 days, hard cook them just as you would cook whole eggs in the shell, drain, and store in the refrigerator in an airtight container for up to 4 or 5 days. It's not a good idea to freeze raw egg yolks because they tend to thicken or gel, getting so gelatinous that you can't use them.
Try this Kitchen Shortcut with Greek Artichoke-Spinach Frittata.