William, 40, and Kate, 41, celebrated the "city's diverse culture and heritage" and as part of their joint outing, they hosted local business owners at an event in The Rectory in the historic Jewellery Quarter.
The Prince looked smart in a blazer, open-collared shirt and trousers, while the Princess wore a pleated burgundy dress from Karen Millen.
The couple's first stop was to Indian Streatery, a family-run independent Indian restaurant based in the city centre, where they helped out in the kitchen and tried their hand at making a handmade roti, a simple flatbread often served with cooked vegetables and curries.
William had everyone in hysterics as he took a booking from a customer over the phone - see the moment here...
The Indian Streatery is run by the Sharma family, led by Head Chef and mum Meena, who came up with the original vision to bring real Indian street food to the streets of Birmingham.
HELLO! spoke with the restaurant's general manager Dhiraj Sharma, who told us exclusive details about the phone call William picked up.
The restaurant, which is home to an all-female chef team, started life as a street food stall in Digbeth and was a firm favourite at the city's Digbeth Dining Club.
During the visit, which comes as part of a wider tour of the country ahead of the King's coronation, Will and Kate said they "love curries" and "secretly try lots of curry houses around the country".
Kate said food is “so nostalgic” and said she "loves spice". Meanwhile, William said he preferred milder food, adding: "I'm a masala man."
When asked whether their children enjoy Indian food, Kate replied: "Absolutely, they love it."
Speaking after the royals departed, Mrs Sharma, 63, said: "It was very surreal and not something you ever think about.
"You never think royalty will come to your humble abode but it's been an absolute pleasure to have them here."
Confirming Kate as the winner of the roti cooking competition, Mrs Sharma, who first came to the UK in 1966 from India, said: "I think clearly there was only one winner, and I think the person who knew they weren't the winner admitted that as well."
The couple's second engagement of the day was at The Rectory, an established pub and restaurant with a rich history spanning back decades.
The Rectory sits on the edge of The Jewellery Quarter, a hub for artistic businesses in the city which produces up to 40 per cent of all jewellery made in the UK.
The Prince and Princess met representatives including designers, artists, and playwrights and heard more about how the sector is growing and their experiences of opening and running their businesses in the city.
William and Kate then joined the guests for a game of interactive darts downstairs in the 180 Club. Check out their concentration faces!
And look who else the couple bumped into!
According to the Court Circular, Kate met with Professor Marc Brackett (Founder and Director of the Yale Center for Emotional Intelligence) and also held an Early Years Meeting at Windsor Castle on Wednesday ahead of her public outing with her husband in Birmingham on Thursday.
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