Just Add Kelly is the tenth episode of Season 3. It premiered on February 1st, 2019 on Amazon Video.
Darbie and Hannah in the previous episode realize that Kelly is the real night bandit, who had been turning into Erin and confronting Mama P for her recipe (Keep the Cookbook Casserole) which could not be made without Morbium. She also stole a pie tin which Chuck used to create the Mulberry Pie (It was a recipe used to stay immortal) which had locked his sister in the book.
After Kelly's birthday party, Darbie and Hannah inform Miss Silvers about Kelly's intentions to keep the cookbook forever, who has been tricking them for weeks. Miss Silvers then considers to call Becky where she is given the quiche to remind Becky of magic. During the conversation Mama P enters where they start discussing the recipes which the OCs had cooked when they were young , In Your Head Banana Bread, which is used to know what is going on Kelly .They realize that they need Livonian Sugar, so they return back to the trailer where Becky stalls Kelly as Darbie and Hannah grab the sugar from the trailer and then they all bake at Miss Silvers house. After baking, Miss Silvers informs the girls to write whatever the want to see with an icing pen.
Then, Darbie and Hannah reach to Kelly's house for their sleepover(which they always do on Kelly's birthday) where they try to stall them from making the recipe till night where they enjoy time with Terri in making Clouds Over Mars, a favorite recipe from their(The trio's) childhood. Whereas, at Springtown,Erin tells Jake about their move to an another town and also that she is going to get married, but Erin actually, wanted to inform Jake about the Pluot bread recipe which has been made into Springtown's menu.
At the Quinn's house, grandma Becky comes over to Kelly's house with an amazing idea in her mind.As she was cleaning up her attic, she finds a bunch Quinn home movies and decides to get a marathon or binge them