Two pies, same mix, different results? Help!
So my sister made some pumpkin pie and had enough mix for two pies. She put half in a ceramic dish and half in a glass dish. Put them both in the oven at the same time and the ceramic one came out perfect but the glass one was not even close to set. She left it in and 2 hours later it's still not set. Now it is obviously overcooked and looks gritty but even so it still isn't set right. What happened? Pie is ruined but we are really curious how the same mix could turn out so completely different.
Any help is appreciated! Thanks in advance.