A great way to store leftover soups and sauces is by using silicon molded loaf mini loaf pans. The kinds that are designed to make small loaves of bread or even large muffins.
These pans make it easy to freeze the leftovers, but also allows you to freeze off individual portions for reheating later.
Place the silicon loaf pan into a sturdy cookie sheet. One you add the soup or sauce, you won't be able to pick up the loaf pan without spilling the contents. That's a seafood stew in the pan. Cover with foil and place into the freezer overnight.
The next day just push the block of soup / sauce out of the molds.
You can place them into a Ziploc freezer bag, but to keep them fresh even longer in the freezer, run them through a vacuum sealer to remove all the air. You can generally keep products in the freezer for 6 months if they're vacuum sealed.