Yes, a thermally insulating material will minimise the heating of the inside. The other problem with those pie tins is that the sides look pretty much vertical, what you want is a sloping edge so that there is some clearance between layers.
Yes, a thermally insulating material will minimise the heating of the inside. The other problem with those pie tins is that the sides look pretty much vertical, what you want is a sloping edge so that there is some clearance between layers.