The best trick, honestly, is to just relax. Over-handling the custard or opening the oven door every five minutes causes temperature swings that lead to cracks. Trust your oven, trust the jiggle test, and trust that a slightly underbaked pie is infinitely better than a dry, cracked one.
I now bake my pumpkin pie at 325°F, let it cool on a towel, and obsessively shield it from drafts. And you know what? Last Thanksgiving, my pie didn’t crack. It was glossy, creamy, and earned me a standing ovation from my family. Well, they were standing for the carving of the turkey, but I’m taking the credit anyway.
