Securing an on Premise non-SharePoint .NET WEBAPI method with o365 Authentication token

We have a custom (non-sharepoint) .NET MVC WebAPI service running on premise.

At a high level, possible somehow to secure methods on that web service using o365/SharePoint Online Authentication tokens?

For example, we only want select SharePoint Online users to have access to a particular method on that Custom .NET Web Service.

Thanks.