The `Not Fair` singer - who last performed in public in August 2010, nine months after the release of her last single - has been focusing on family life with husband Sam Cooper and daughter Ethel, seven months, but has now returned to the recording studio with producer and previous collaborator Greg Kurstin.
She tweeted: "you will be pleased to know that i am currently in the f**king studio with @GregKurstin
"no big deal really, im just throwing s**t at the wall and seeing if anything sticks.(sic)"
Meanwhile, Lily joked that she plans to divorce Sam - who she married in June 2011 - after hearing Johnny Depp has split from long-term partner Vanessa Paradis.
She tweeted: "FFS , Johnny Depp is single, and i`m married ? *calls divorce lawyer*
"only joking I love my husband more than words can say.(sic)"
Lily previously admitted she missed performing live but knew it was important to put her family first.
Speaking when she was pregnant with Ethel, she said: "When I go to gigs and stuff, I get a slight pang of envy and I think, `Oh I do miss being up on that stage.` But I have other priorities at the moment."