The Apprentice star, 25, looked gorgeous in the colour when she attended the Shooting Star CHASE Ball last night (Oct 5).
Arriving at The Dorchester Hotel in London's Mayfair, Luisa showed off her killer figure in the grey fishtail frock by Aurelio Costarella.
But the event wasn't about looking good; the celebs were there to raise money for the care and provision of terminally ill children across London, Surrey and West Sussex.
Luisa raised an impressive £3,000 by donating a date with herself!
The Apprentice finalist and baking retailer also found time to lark around on a pink mini-Vespa signed by girl band Stooshe, which Luisa bought for £2,400 for her daughter.
She tweeted: "I got [the scooter] in the auction. Dixie is now very happy with her new gift - I think I like it more though."
Last year, the annual fundraising ball for Shooting Star CHASE, raised £191,000.
The hospice charity, whose patrons include Chris Evans and Joan Collins, help over 600 families with terminally-ill children.
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