Nick Jonas made a heart-shaped pizza for his rumoured girlfriend last night

The Jonas Brothers singer prepared the romantic culinary treat for his 'Les Miserables' co-star Lucie Jones, 17, at a Pizza Express restaurant in Soho, London, to mark one of their final nights out together before he returns to Los Angeles after completing his run in the stage production.

The crusty Cupid had asked the eatery if the pair could come in one night after closing time for the unique date before he flies back to the US.

A source said: "He put in a request to the restaurant. He specifically asked for a midnight pizza-making session for him and Lucie. She was thrilled with the effort he made and the pizza he made was delicious as well."

The 17-year-old singer is reportedly keen to keep his romance with the Welsh beauty – who shot to fame after appearing on UK TV talent show 'The X Factor' – under wraps as he doesn't want to upset his legions of fans.

A source said: "Nick is pretty smitten but nothing is official yet not least because his fanbase would be gutted if he was to announce he was no longer single."

Nick later tweeted about how much fun he had had making the pizzas topped with love.

He posted: "What a great night. Thanks Pizza Express for the good times. Goodnight everyone. Love you all."