Blend until perfectly smooth, scraping sides occasionally, and adding extra milk if the batter is too stiff. (havecakewilltravel.com)
You can add a little extra milk in if your child prefers it more liquid - y like my daughter! (corinanielsen.com)
A pump also comes in handy for storing extra milk for use down the road when you need to get out of the house or when you head back to work. (mymommystyle.com)