Darren McGrady - who worked as Her Majesty's resident cook for more than a decade - opened up about the Queen's culinary preferences to US Weekly, telling the publication that garlic was banned from Buckingham Palace.
'She hated the smell of it, she hated the taste!' he revealed.
The gastronomic genius said strong smelling sauces and messy dishes were also forbidden, including shellfish, ketchup, onions and curry.
Queen Elizabeth, who is 92, was given a red leather menu book by McGrady with a list of options each day.
The former royal associate said the Queen's favourite dishes included steak with mushroom sauce, gamey entrees like duck or pheasant and smoked salmon pate.
According to McGrady, HRH is a creature of habit who 'stuck to the same dishes week in week out'.
But despite her rigid restrictions on certain food stuffs, the chef recalled there was one meal the monarch rarely skipped: dessert.
'[She'd choose] anything on the menu that had chocolate, especially chocolate perfection pie!'
McGrady also remembered the royal protocol for shapes, which prohibits square sandwiches based on the medieval belief that anyone presenting a monarch with pointed-edge food is 'trying to overthrow them'.