Kasma Loha-unchit leads trips to Thailand. I only know of this through her website and haven't been on a trip. I do like her cookbooks very much.
While the trip is a 'cultural' trip - food seems an important part:
Kasma Loha-unchit has taken small groups (12 people maximum) to experience her native Thailand since 1986. These groups have consisted of friends, neighbors, cooking students, their families and friends, and other interested people who know her through her book or from friends who have travelled with her, She characterizes these as off-the-beaten-path adventures for people who want to get to know true Thai culture.
These trips are not for everyone. Food is an important part of the trip and participants must love spicy Thai food. They are designed for independent, physically active people in good physical condition who enjoy spicy Thai food, rice and fish, eat food of all kinds, don't mind rising early occasionally or roughing it when necessary to see beautiful sights. We cannot accept anyone who has special dietary needs – including food allergies, strong food preferences or not eating a specific food be it animal (pork, chicken, fish, shellfish) or a vegetable, such as onions. The groups travel in two mini-vans and are more reminiscent of friends or family traveling together than a package tour. They are especially designed for Thai food lovers who love to eat everything – we feast on Thai food every day of the trip.
The trips always take place between November and February.