2. Wrong Oven Temperature
With custard-based pies, it’s all too easy to get the temperature wrong. If you bake at too high a temperature, you wind up with a scorched pie. If you bake at too low of a temperature, you wind up with an underdone pie that no one really wants to eat. (That’s the worst, when your family or guests take a bite, put their fork down and politely declare it’s delicious but they’re too full to eat any more.
No one should be able to resist a sweet potato pie!) You may need to vary the temperature as you go. Check your pie every ten minutes or so to make sure it’s cooking evenly, and the temperature doesn’t need adjustment. It’s tempting to just pop it in the oven, go on about your business and leave it until the timer goes off, but you’ll get better results by monitoring your pie. Somewhere between 375 F and 425, F is about right, depending upon your oven. Bonus points for knowing whether your oven tends to run hotter or cooler and being able to adjust!