The right perspective when it comes to culture is then the same as the one for ideology: to develop an approach in which cultural factors interact with institutional and political ones.
The context of the quote is important, it is from a post by Acemoglu and Robinson.
I used to think that culture and institutions are the same thing [others think that institutions and policies are the same thing]. But if they are not, there are repeated instances in which it is difficult to find the border between cultural practices and informal institutions. There are instances in which institutions transform themselves into cultural practices, and vice-versa.