This is a book I read in the mid to late 60’s about a young girl who goes to live with her Aunt Meg, who she finds out is a witch. The little girl finds a stone which belongs to another witch named Lanie. They try to get the stone back. I think there is some magic food involved and I believe the stone helps the little girl fly.
Stump the Bookseller
New format, same book stumper solving.
A long shot, but look at Sneaker Hill.
https://www.amazon.ca/Sneaker-Hill-Jane-Little/dp/0689714777
Close, but no. Sneaker Hill was published in 1991. The book I read was circa 60’s to 70’s. The storyline is different as well. The Aunt’s name is definitely Margaret because they call her Meg for short and she’s not studying to be a witch, she’s already a witch, the head witch if I remember correctly. Thank you for your suggestion though!