Response from Ant贸nio
In Aveiro when you want "tripas" what you get is an undercooked soft cookie. The place I pointed you to was the right place for that. I even told him that "tripas" were a sweet tradition in Aveiro that was around 50 years old, unlike "ovos moles", a conventual sweet that is more than two centuries old.
The other "tripas" are not a traditional dish from Aveiro, but from Porto.
I regret this obvious misunderstanding. Next time I'll try to tell you if there are any restaurants in Aveiro that serve good "tripas" in the Porto style.