A cognitive walkthrough is a great method to do before performing another type of user test. In my experience, this is good to do before a Flash or RAW test because it allows us to be able to get to the heart of what we want to know, what should be tested, and can help us pick the correct follow-up test method. This can also be done as a stand-alone test without planning a future test if you are looking for raw feedback from a number of individuals before formulating a plan to do more user testing or how to move forward with a project.

The process of a cognitive walkthrough is to go through an application or website (or even just a small portion of one) and perform the tasks that have been written for users. This can be done in a group setting or individually and then bring those who tested together to discuss. Discussion is a big part of this method so that you can understand what those going through the test are thinking and potentially open the floor for suggestions on how to do something differently within what is being tested.

More information on the cognitive walkthrough method:

https://medium.com/user-research/cognitive-walkthroughs-b84c4f0a14d4

https://www.interaction-design.org/literature/article/how-to-conduct-a-cognitive-walkthrough