Transport network virtualization provides the necessary data and control plane technologies as key enablers of future networks. The interaction between network slicing and optical transport network virtualization architectures is under study to automate effective network resource orchestration. In this paper, we present an harmonized network slicing and transport network virtualization architecture, including a network slice planner tool, which is designed and implemented enabling in-operation execution of network slice resource allocation algorithms. We validate the proposed architecture by providing a novel resource allocation algorithm, evaluating its performance and deploying two different slices on top of the ADRENALINE testbed, while measuring both slices key performance indicators.