Not very long ago, organizations used to identify their customers by means of one-factor authentication mechanisms. In today's world, however, these mechanisms cannot overcome the new security threats at least when it comes to high risk situations. Hence, identity providers have introduced varieties of two-factor authentication mechanisms. It may be argued that users may experience difficulties at time of authentication in systems that use two-factor authentication mechanisms for example because they may be forced to carry extra devices to be authenticated more accurately. This is however the tradeoff between ease-of-use and having a secure system that may be decided by the users and not the security providers. In this paper we present a new two-factor authentication mechanism that secures systems and at the same time is easier to use. We have used mnemonic features and the cache concept to achieve ease-of-use and security, respectively. Also, we have tested our method with almost 6500 users in real world using The Mechanical Turk Developer Sandbox.