The test execution infrastructure of TFS has been improved a lot, so for now it is also possible to execute automated test cases on test machines (e.g. on Azure VMs) from the TFS web interface. You do not even need to install Microsoft Test Manager for the execution. There are neat features for this (like distributing the test executions to multiple machines), but the best of it is that the test cases synchronized from SpecFlow scenarios by SpecSync all support this.
SpecSync for MTM is a synchronization tool that integrates SpecFlow to TFS/MTM. It can synchronize your scenarios to TFS test case work items. If you would like to learn more about SpecSync, check out the getting started guide in the documentation or watch our new getting started video on YouTube! We have just released v1.2!
To be able to execute the TFS test cases synchronized from SpecFlow scenarios, you need to create a build that compiles your application, copies the deployment package to the virtual machine(s) and executes the TFS test agent to run all or just selected scenarios. The executed scenarios can be specified by Test Suites within a Test Plan.
Check out the video that demonstrates how this works.