Chop however many onions you would like (I like Vidalia when they are available). Put a bit of olive oil in a heavy skillet, along with a little butter, and sautee onions until they are to your preference. Take out of skillet to cool and when cool, put them in ice cube trays, cover with plastic wrap and put them in the freezer to freeze. When frozen, pop them out and place in a zipper bag and put back in the freezer. Now you have nicely proportioned onions ready when you need them – without all the fuss.