Eugenia Potter series by Virginia Rich (picked up by Nancy Pickard)
Cooking School Murders
In Harrington, Iowa, for her yearly hometown visit, dignified and down-to-earth Mrs. Potter becomes involved in the slashed-throat murder of a student in an advanced cooking class attended by Harrington's elite. We are introduced to Eugenia Potter and the other cast of characters. It is interesting as I read these many years ago and am enjoying it very much.