The 16-year-old singer, who was booted off the ITV competition last month, confirmed that she had beaten runner-up Jahmene Douglas and boyband Union J to landing a lucrative deal.
"Hopefully this time next year I'll show people why I'm here. I'm so excited to go into the studio and do what I've always wanted to do," she told RTE's Saturday Night Show.
"I've written stuff already but I can't wait to write new stuff," she added.
Ella, who is being managed by her dad, later told her Twitter fans: "Thank u for your messages :) #JustTheBeginning ;) xx"