Making pie from left offer casserole

[Greycat11]

I'm going to make a pie tonight with left over chicken casserole I cooked in the slow cooker yesterday.
Do I need to reheat the filling and get it piping hot before I put it in the pastry or will the cooking in the oven be enough to reheat it safety?
I'll be using shop bought ready rolled fresh pastry which I think needs about 20 mins to cook. Thanks in advance for any help

It should be fine from cold, it might melt the fat in the pastry if it's too hot.

Wi do this quite often, with the filling cold. Sometimes bulk it out a bit with some extra thinly sliced veg like carrots or potatoes or mushrooms.

It will take a bit longer than that to cook. Depending on the size of the pot. Is it just a lid?

I've always found that the top doesn't cook until the middle is hot. If the top is nice and brown, the middle will be hot.

It will take longer than 20mins though. Mine is more like 40, but it is quite big.

Thanks all. I like the idea of bulking out with some extra veg.
I was planning on just using a flan dish, and having a bottom and top but don't have to. Just the lid idea has given me an idea, maybe I could cook the pastry separately and add as a lid after?

Yes, that works, though it doesn't feel quite as comfort foody, IYSWIM. We usually only do lids, not bottoms.

Turned out nice, thanks all. Layer of extra veg (mushrooms) was nice.
Will also probably just do top next time as bottom was a bit soggy. Maybe I was meant to bake that blind or something but won't be doing that!

Bottoms need shortcrust pastry and a really dry filling- corned beef and potato, say. If you want a saucier filling, you need to bake blind which is go able but adds an extra twenty mins and an extra job so I never do.

Tops are fine in shortcrust or puff, wet filling or dry.

Thanks Pickle, that's good to know. I like the sound of the potato and corned beef pie. I never cook with corned beef but now I'm craving corned beef fritters like my DM used to make which I'd forgotten all about. Going to try to replicate them as think my DD would like them too.