Does anyone know the name of this book?

Children's book, it had a red cover. I'm a bit hazy on the details, but I know it had some sort of jewel hidden in a barrell of flour, a community of witches & a young girl witch who was sort of the protagonist, footprints, and hiding in a bath under an old rag. Lol I know it sounds pretty rubbish but it's actually a good book. There were two mysterious figures, one big and one small as well. Any help (if you can make sense of my ramblings) would be great, I really want to find this book!