You should squeeze out as much liquid as possible. My cousin and I disagree on the following approach, that is my friend’s mom’s approach to avoid sogginess- add rice.
Something like this recipe
https://more.ctv.ca/food/recipes/spinach-pie0.html
My cousin now adds rice. I don’t.
My issue with frozen is that the egg and feta can’t get between the leaves of spinach. It’ll be a slightly slimier mouthfeel with frozen spinach, but many ppl are used to that, and some ppl like that. I would just buy good frozen burek or frozen spanakopita (at Greek stores, at TJ’s, at Canada’s Farm Boy, at Cdn Costco - some good frozen ones are imported from Greece, Macedonia and Bulgaria, my local Polish store also carries them) , rather than make a good burek or spanakopita with frozen spinach.
I only use frozen spinach for one thing: Knorr Spinach dip in a bread bowl.
This is a way I’d be more likely to use frozen spinach for this thread
