Coffee/Lunch at Muffin Break

The recently opened Muffin Break in Worthing provide exceptionally good, and some unusual food (not just muffins) and coffee. They don't take bookings, but it has a lot of seating, so that is unlikely to be a problem. It's one I use a lot, so I personally recommend it.

https://muffinbreak.co.uk/store/worthing-montague-street/
"We take our mission for providing good food seriously. That’s why each and every item on our menu is handmade. Our expert bakers start everyday bright and early, by freshly baking our selection of sweet and savoury items in our onsite kitchens.
But our passion goes beyond that. To produce delicious food the best quality ingredients are required, sourced locally where possible and inspired by the seasons. Our menu is designed to cater to a range of tastes, appetites and dietary requirements including gourmet pies, quiches, wraps, cakes, scones and cookies as well as our famous muffins."