The Chocolate Cat by Sue Stainton, illustrated by Anne Mortimer

From chapters.ca:
In a drab village nestled between the mountains and the sea, an old chocolate maker lives alone with his cat, making uninspired chocolates to display in his dusty shop.
One day he does something different and makes chocolate mice with crunchy pink-sugar tails—but he won’t eat them. Cat soon discovers there’s something truly special about these little mice, and everyone who tastes them is inspired to create something new and different, something the little village has never seen.