Matilda's Homemade Cherry-Nut Wafer Nibblets is a food from the episode Judge Mia's Valentine's Day. Matilda sent it with Maggie to school for the Valentine's Day party. Mrs. Dotter found it delicious, but it gave her extremely severe constipation afterwords.
During the episode, Maggie calls the food "Cherry-Nut Nibblets", excluding the "Wafer". This could be a mistake or just a simple variation.