In Ni no Kuni 2 there's some fantastic items you can get from side quests that will help you in combat. The Ni no Kuni 2 Rosehip Tart is such a recipe you can cook up!
Where to find Rosehip Tart quest?
You'll be given a side-quest called ‘A Secret Sweet Tooth' - it's mission 55, and you'll discover it from Chapter 6. The quest can be found in Goldpaw, and you'll need to fetch the Sweet-Toothed Man the Rosehip Tart.
How to get the Rosehip Tart?
With a rarity level of 5, you're going to need a fully upgraded cookshop. Even though you can pick up the quest at Chapter 6, it's likely you'll be near end-game before you can complete it.
Make sure that Tasty's Cookshop is upgraded to the max, and cook as much food as possible to boost your cooking level. Once, you've done that you'll be able to make the tart.
What does the Rosehip Tart do?
Though it can only be cooked near the end of the game, the Rosehip Tart is a great item. Not only can you now complete the ‘A Secret Sweet Tooth' quest, but you can use this item in combat to boost your charged attacks more rapidly.