OK, so I know after the day I have had I shouldn't have tried to cook anything at all.
I've tried making vol au vents from bought puff pastry. Every single time I have done them (3 batches in all), they are uneven. One side rises more than the other. And they are impossible to do anything with.
I've tried doing big ones, small ones and square ones and after the first batch were a disaster I tried cooking them in the ordinary oven rather than the fan oven, but nothing worked.
From the BBC website:
"Brush a little beaten egg mixed with a pinch of salt over the top of the cases, making sure not to cover the sides. This would prevent the pastry from rising up evenly".
So are you applying beaten egg to the sides, as well as the tops, perhaps?
http://www.bbc.co.uk/food/techniques/how_to_shape_and_fill_vol-au-vents
I am with anneasquith .... buy the frozen ones .................no different if using bought pastry anyway but guaranteed to work ............... and after all it's the quality of the fillings that count :-)
Get the other half to pop a spirit level on the oven shelf.
If the shelf is level, no way would you have to turn them.
My built in oven was out by about 1mm. Sorted now.