Cut the apples ahead of time. Save them in a ziplock bag with plenty of lemon juice and all the air squeezed out. The citric acid slows oxidation and you've removed most of the oxygen.

Cut the puff pastry to size ahead of time. Wrap in plastic and store in fridge.

I think you could do the above a day ahead and then quickly assemble and bake.

And an alternative recipe.

Peel apple. Core it. Mix sugar and cinnamon. Roll apple in mix, pour mix into cored apple to fill. Place on a large square of puff pastry. Wrap pastry up around apple, gather at top in a pretty ruffle, tie with a bit of kitchen twine. Bake 350F for 40 min. Stick a paring knife into an apple to judge doneness, might need up to 10 min more. Snip and remove twine .

I usually do this with phyllo but that takes more time .

This post was edited by johnliu on Thu, Dec 19, 13 at 19:31

Thanks johnliu! The apple dumpling is a good idea!
I've also been thinking about an apple pie, but in a vegan graham cracker crust. I could make that the day before, I think. Or even an apple crisp. I bought my daughter some vegan ice cream too.
I sure wish my kids would start eating meat and dairy again. haha
It would sure make life easier! But I do respect their choice. My son is a vegetarian.....which is easier to cook for than a vegan.
Thanks again John.

Be careful to ensure the puff pastry is vegan- traditional puff pastry is made with butter and so not vegan.

The pepperidge farm brand is considered vegan by some. It does not use butter but is not considered very vegan by the organic purists.

Unbleached Enriched Wheat Flour (Flour, Malted Barley Flour, Niacin, Reduced Iron, Thiamine Mononitrate (Vitamin B1), Riboflavin (Vitamin B2), Folic Acid) Water, Partially Hydrogenated Vegetable Shortening (Soybean and Cottonseed Oils Colored with Beta Carotene) 2% or Less of: Gluten, Mono and Diglycerides (from Hydrogenated Soybean Oil), Soy Lecithin.

If i attempt tp make something to please everyone, i'll use philo and build layers using organic ingredients. DH has made from scratch before, though can be tedious. Still can be annoying...if my sister gets preachy and cranky, i just hand her the blender....she can make whatever blended smoosh she wants.
I only cater so far and often have fun trying. Cynical with a smile.

If the puff pastry you use is ok, no reason you could not prep the apples and filling by slicing and heating in a saucepan with the sugars and citrus...lemon etc, a day or two before. Assembled and baked hours before the meal, then re-heated. All sorts of puff pastries displayed in bakery cases, then sold and consumed later that day or the next by re-heating...also see many in the freezer section. Most are baked halfway, then frozen. Final puffing/crisping in the oven.
Puff pastry is festive. I rarely use it as a standard ingredient but will next week for mostly savory dishes and maybe a sweet using blueberries and raspberries from the summer harvest.

Baklava.
Ingredients
18 sheets ready-made filo pastry (unwrap and keep under a damp tea-towel until you are ready to use)
225g/8oz unsalted butter, plus extra for greasing
225g/8oz mixed pistachios and walnuts, roughly chopped
2 tbsp granulated sugar
1 tsp ground cardamom
For the syrup
350g/12oz granulated sugar
300ml/10ýfl oz water
1 tbsp lemon juice
2 tbsp orange blossom water
Preparation method
Preheat the oven to 180C/350F/Gas 4.
Grease a 17cm x 28cm (11in x 7in) baking tray with butter.
Melt the remaining butter in a saucepan over low heat or in a microwave.
Lay 10 sheets of filo pastry, one at a time, into the tray, brushing each sheet with butter before adding the next.
In a clean bowl, mix together the nuts, sugar and cardamom and spread the mixture over the pastry in the tray.
Layer up the remaining sheets on top of the nut mixture, brushing each sheet with butter, as before.
Using a sharp knife, cut a criss-cross pattern into the top layers of the pastry.
Place baklava in the preheated oven for approximately 20 minutes, then decrease the oven temperature to 150C/300F/Gas 2 and cook for an additional half hour to 40 minutes, or until the pastry is slightly puffed and golden on top. Do not allow the top to burn. Remove and allow to cool slightly.
For the syrup, heat the sugar, water, lemon juice and orange blossom water in a small, heavy-bottomed saucepan and cook over a medium heat until the sugar has melted and a syrup is formed. (This will take about 20 minutes or so.)
Pour the syrup into the slits in the baklava and leave to cool. Cut into small diamond-shaped pieces and serve.