If you're fostering puppies between 3 and 7 weeks old, puppy gruel is the secret weapon that bridges the gap between milk and solid food. In this step-by-step guide, we'll show you exactly how to make it in a blender in under 10 minutes — plus how to make no-blend puppy mush for older pups. Get ready for the messiest (and most rewarding) feeding sessions of your life.