beach brownie
A beach brownie is the sand-encrusted excrement of a child who, while playing in the sand, digs a shallow hole and deposits his present.
Most commonly, the beach brownie is discovered by an unsuspecting and gullible child who, while merely digging the moat for his sandcastle, uncovers the now sand-encased and hardened deposit. The magellan-child exclaims, "Mom, I found something," to which the parent shakes her head and remarks to a fellow parent, "Billy found another beach brownie."