Wiktionary
mud pie
alt. A mass of mud shaped into the form of a pie, especially by children n. A mass of mud shaped into the form of a pie, especially by children
WordNet
mud pie
n. a mass of mud that a child has molded into the shape of pie
Usage examples of "mud pie".
Gus's horse, a big solid sorrel they called Mud Pie, and was catching his own mount.
She nevertheless sat down opposite Harvey, stuck her thumb in the mud pie, and licked it clean.
The answer's in there somewhere, but it's murkier than mud pie stew.
It was in black and white, and it did look a little like a close-up of a mud pie.
Pace like a mud pie, figure like a gunnysack-only on an outpost like Mars could she get by.