How do I access methods in ViewController.swift from within my AppDelegate.swift?

Class ViewController:
{
    // Using a property
    var firstName: String!
    func printSomething(name: String)
    {
        println("Hello \(name).... All your base belong to us!")
    }
}

Class AppDelegate: UIResponder, UIApplicationDelegate
{
    // View controller instance, this is the hook to your ViewController
    var vc = ViewController()
    func application(application: UIApplication, didFinishLaunchingWithOptions: [NSObject: AnyObject]?) -> Bool
    { 
        vc.firstName = "Jared"
        // This is calling the function from the view controller
        vc.printSomthing(vc.firstName)
        return true
    }
}