In Galicia, empanadas are not the same as what the rest of the world thinks. Here they are large pies essentially, and filled with local ingredients like seafood.
There aren't many bakeries in O Grove, but Castro's seems to have the nod with also all the locals queuing there for their morning bread each day. They probably don't get a lot of tourists, because even the locals seemed amused/surprised to find me there (and speaking some Spanish).
I tried the cockles (berberechos) empanada €12 - a thick buttery pastry with lots of cockles filling the inside. It had good flavour. My only small gripe was it was quite gritty too.
Upon leaving at the end of the trip, I had a mussels (mejillones) €7 to go. Although the local mussels are great, these were slightly less in terms of quality and flavour (obviously used for this purpose) but still good. And not gritty either.
If I'm ever in the area (which is quite unlikely to be honest), I will be back at that bakery.