Help me with a puff pastry pie lid question please!

[GammonAndEggs]

I’ve blind baked a shortcrust base.
my pie filling is cold.
I want to add a puff pastry lid.

Do I need the base and filling to be warm before I put the lid on?

No it can be done hot or cold.
That said some fillings work better cold

No. If the pastry case and the filling are cooked and chilled, just add the puff pastry lid and cook it all together. If it's a very deep or large pie you might need to turn the oven down once the top starts browning to give the filling time to heat through fully (which also results in crispier puff pastry).

Thank you!