My meal planner! I like having everything on one piece of paper for ease, so I try to make all my planners as simple as possible to allow for that. I used to have two other sections on a separate paper for brainstorming and planning what to prepare ahead of time, but decided that those two sections were unnecessary. However, having an extra paper for those might be something helpful for you!
Something else I highly recommend is ordering groceries online for pickup. It can help you save time, and in my case save money. It curbs my need for impulse purchases, keeps me on my budget, and gives me more free time to do other things, like cleaning.
I'm currently trying to compile a digital pantry for my apartment, as well as a digital cookbook full of recipes for people living on their own, ranging from simple and easy (bagel pizza!) to more complex (homemade cheese and bread!) Overall, I'm hoping by documenting all of these things I'm doing to improve myself, I can help someone else who feels like me.