It's Berry's first trip to the Pastry Kingdom. Her classmates have all gone home, leaving Berry alone, and Vanilla invites her to go, and it's also the episode where she meets Berry's grandmother's genie and gets the key to open the secret recipe (which is a silver spoon)

Episode 46:

Kenno borrows a book with the same recipe as the one left behind by Berry's grandmother. In episode 39 it was Berry who opened it with a spoon) as well, both books have the same pixie fairy dust and the page recording the recipe for the strawberry tart has disappeared, Berry decides to go to the Pastry Kingdom and retrieve the secret recipe, but Kenno is against it, later Berry listens to his grandmother's pixie (also known as the librarian) and gets the secret recipe, but understands the need to create her own strawberry tart that surpasses her grandmother's. So didn't look at the secret recipe

Episode 55/56/57:

This is the first time anyone other than Berry goes to the Pastry Kingdom because of an accident, both Chocolate and Vanilla wanted to try out the new magic, which led to Berry and the girls getting involved, and it was pretty fun for them to explore the Pastry Kingdom together, and Kenno got inspired by it to come back and create a new dessert

All of the above was taken from /question/386391886.html

Thanks to user 92654222 for the answer

Looking forward to adopting it