She said: "I have two lives - a country life and a London life. In the country I cook almost all organic. We never eat anything out of packets. I have eggs from my own chickens and bacon from my own pigs.
"In London I go out to dinner almost every night - all I have in my fridge is a bottle of vodka and eye masks."
The Royals star - who has 13-year-old son Damian with former partner Steve Bing - admits she has a penchant for sweet treats and loves to make her own calorific offerings on a weekly basis.
She added to Star magazine: "I make jam every weekend and I make puddings and desserts at home, but only twice a week."