The Hubb Community Kitchen said Meghan left a “lovely voice message” and asked “how we are, about our children and families and giving us news of hers”.
In a Facebook post, the group said the duchess – mother to Archie and Lili – was “just being her beautiful kind self”.
The Hubb Community Kitchen evolved after a group of local women affected by the devastating 2017 fire gathered to prepare fresh food for their families and neighbours in the aftermath.
Meghan collaborated with volunteers by supporting the creation, and writing the foreword, for their award-winning charity cookbook Together: Our Community Cookbook.
The Kitchen’s post read: “I just found this picture of us all, on the day our cookbook came out. The Duchess had wrapped a book for each one of us and wrote a lovely message to each lady on the first page.
“Always very thoughtful, today we received a lovely voice message from the Duchess, being the 5 years anniversary of the Grenfell tragedy, asking how we are, about our children and families and giving us news of hers.
“Just being her beautiful kind self.”
Meghan was back in the UK for the Platinum Jubilee earlier this month with the Duke of Sussex, Archie and Lili.
She made an appearance with Harry at the service of thanksgiving held to mark the Queen’s milestone.
Kate and William were among those who observed a 72-second silence at the base of the tower in north Kensington, London, in memory of the 72 men, women and children who died.