A few weeks ago I made some homemade ice cream sandwiches for Nathan's birthday. There was homemade lemon ice cream with molasses/ginger cookies (which seems to be our favorite flavor combo lately) and Tillamook vanilla ice cream with oatmeal chocolate chip cookies. Here's a few tips I learned while making these in case you want to make some too:
1. Melt the butter in the cookies before it's mixed with the sugar. The warm butter will help make the cookies flatter.
2. Freeze the cookies prior to making the sandwich part. They aren't as fragile then.
3. Scoop the ice cream (not too melty, but not too hard either) with a small cookie dough scoop. It's easy to control the portion and the sandwiches end up with about an inch of ice cream.
4. Press both cookies and ice cream together slightly so it all sticks. Then refereeze till your ready to eat!