You can build a recipe that incorporates your shake and the additions to it. First, make a custom food for your shake, using the information from the label. Then, go to a blank day in your food log (in the future), add the shake, oats, and banana, and then take the resultant totals to create your new custom food that incorporates all those things.
"If you drop an egg, you don't say, 'Oh, shoot' and drop the other 11, do you?"
-Source unknown, but obviously brilliant
Reached goal 4/16/2010...but kind of afraid to look these days