Financial analysts are very organized and methodical. Sticking with a process in your reporting is essential to your efficiency and consistency. Your interviewer is interested in the aspects you consider in your research to prepare your reports. There is a structure most reports follow.
Talk about the basic structure of your report to show that you know your audience. In this example, you are thinking about investors, which will affect the layout of your report and the information you include. Review one of your most recent reports to refresh yourself on your process.
"I start with a company overview, investigating all of the deciding factors an investor will need. I often include this information in my investment thesis. Next I will include the key risks and valuation. I am thorough and make sure I have reviewed every aspect of the business to help investors make an informed decision."