MARY-KATE and Ashley Olsen have developed a sweet tooth after investing millions in Los Angeles' cake shop Sweet Lady Jane.

The millionaire twins have reportedly invested $2 million (GBP1.1 million) in their favourite bakery.

It's not the bakery's first brush with fame - Sweet Lady Jane's bakers have created wedding cakes for Jennifer Lopez, Bruce Springsteen and Carnie Wilson.

Mary-Kate and Ashley are said to be so involved in all aspects of their new business, they've even started coming up with cake ideas for Sweet Lady Jane founder JANE LOCKHART, according to American publication In Touch.