How far in advance you making the pork? If you cook it say, 2 hours ahead of the time you want to serve it, then just leave it at room temp instead of placing it in the fridge. The puff pastry needs to be chilled, so that can stay in the fridge until you need it. If you're cooking the pork, say, 5 hours ahead, you'll need to refrigerate the it. To reheat the pork evenly, place it in a stainless steel mixing bowl or container and reheat it using a double boiler method until it's just warm. Do NOT microwave it. Then, place it in the cold puff pastry and bake as normal
I wouldn't recommend cooking it at a lower temp because the puff pasty may not rise and cook properly.
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