Asp.Net Core Identity - Authorize attribute with roles and caching?

I have a simple web application in ASP.Net Core with ASP.Net core Identity. I'm using role based authorization on various controllers and it seems to me that the Authorize attribute is not picking up changes to role membership right way.

Let's say I decorate a controller with the authorize attribute and specify a role, like this:

[Authorize(Roles = "TestRole")]

Then I log in as a user which is not in that role. I try to access the controller and the Authorize attribute correctly prevents me to access the controller - gives me an access denied error.

Then I add the user to the TestRole programmatically (I have built a simple user management GUI in the web app where I can manage users and roles). According to the GetRolesAsync() method, the user has successfully been added to the role and everything looks good if I check the records in the Identity tables in the DB. However, I still cannot access the controller - the Authorize attribute does not seem to be aware that the user is now in this role. The role information seems to be cached. If I wait long enough before trying again (a few hours maybe) then this appears to work correctly. If I kill the IIS express process and restart the website, this works immediately, suggesting that the role information is somehow being cached.

I have not been able to find anything which explicitly states that the Role information is indeed cached or how to disable it for that matter. When I change the role membership of users in my system I need the changes to be reflected right away.

Any ideas?