Here is a shot of the purees I most always have on hand in my freezer, thanks to Jessica Seinfeld's book;  Deceptively Delicious.  The two shown are the most popular one's in our kitchen; butternut squash and spinach puree.  I love making these little purees, not so much to hide veggies from my children, but because they really make any sauce heartier and taste better.  And, they increase the nutrient and fiber content of anything they are added to.  I know I am always striving for that!!  The butternut squash and spinach neutralize the acidity in tomato sauces so they are perfectly balanced, while the cauliflower puree beautifully fluffs up scrambled eggs.  To make my purees, I pretty much follow Jessica Seinfeld's directions in her book.  For example, with spinach, I barely steam it in order to retain as many of the nutrients as possible.  As soon as it starts to wilt, it goes into the food processor.  Once it is evenly pureed, I let it cool, then measure out half-cup portions into ziploc snack size bags and freeze flat in the freezer.  Once they are frozen solid, they store very neatly standing up in the freezer door compartment or a small container set on one of the refrigerator shelves.  They can easily get lost and forgotten about if not contained!  Believe me, I have learned the hard way!!  If this is a new practice to you, make sure your purees are placed neatly in a spot in your freezer that is visible every time the freezer door is opened. Seeing them will make you want to use them and once using them becomes a habit, you won't see how you lived without them!