A bale of quince harvested when Halley's comet is in the sky
Crushed toes of pigeon
A mixing bowl of sage harvested at dawn
1 cup of sieved brains of lizard
3 tsp desiccated brains of newt
A purse of truffles gathered at the full moon
Turn into cupcakes, then fry in the cauldron with some cat sick.
Induces young heroes on quests to grow long tails and start whinnying, and makes small donkeys fall in love with you.