Multi-tenancy is a key to successful and sustainable cloud-based systems. Creating a web application framework for multiple tenants from scratch is challenging. To create an extensible, stable and robust multi-tenant web application framework developers have to understand how a web application framework is structured and how a web request is handled for each user of a specific tenant. This knowledge often takes software architects and developers a lot of effort to obtain. In this paper, we present a novel object-oriented architecture pattern for developing multi-tenant web application frameworks in which maximum reuse and modularity can be achieved and application concerns can be separated. We evaluate the modularity, the extensibility, the reusability, the maintainability and the efficiency of our pattern by qualitative analysis based on well-known patterns used in our pattern. We validate the applicability, the correctness, the security and the performance of our pattern by testing real world systems that were built using our pattern. We believe that our pattern would reduce time and cost when developing multi-tenancy systems as well as understanding, evaluating and modifying existing web application frameworks.