Hillingdon Autistic Care and Support (HACS) run the cafe in Uxbridge to give work experience, training and skills to help people lead more independent lives.
The Foreign Secretary officially opened the project at the Brookfield Adult Learning Centre, joined but Hillingdon councillors, the HACS team and people who work at the cafe.
Former Mayor of London, Mr Johnson , said: “I know what a wonderful job HACS do and what a fantastic service this is for people who want to learn, to develop and have fun in all sorts of ways.”
"Is this a fantastic cafe?," Mr Johnson asked the crowd, who resoundingly answered with a chorus of "yes".
"Yes it jolly well is," Mr Johnson said before officially opening the cafe.
HACS has a similar cafe at the Rural Activity Garden Centre in West Drayton called the Rural Tea Room.
There are 22 people currently participating in the cafe project and so far seven have gone on to find secured paid jobs.
HACS are now extending the service to 40 young adults thanks to funding from Hillingdon Council and are looking for local business to offer work experience opportunities.
Chief Executive of HACS, Antoinette Mullally, said: “Less than one in six autistic adults are in full-time employment, yet we know that people with autism want to work and contribute to society.
“We are working to close the gap between autism and employment and make employers aware of the valuable skills people with autism can offer.”
Employers interested in helping HACS can contact firstname.lastname@example.org .
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