If your account is connected to Facebook, Twitter, and/or Google, simply use your login credentials from one of those services to login to Kinja.
Burner keys cannot be recovered. Burners are designed to be anonymous and completely secure; the only time the key is displayed is at sign up, and only to you. Additionally, Burner keys are not stored on our servers, thus we cannot aid in the recovery of your key. Please read this for more info.