If you’ve got a cake or pie in servingware you don’t want scratched or marked by metal utensils – like the bottom of a non-stick springform pan or a pretty ceramic pie plate – use a sturdy plastic knife to cut your baked goods instead!
If you’re a parent there’s a good chance you’ll have a set of IKEA inexpensive but strong plastic cutlery around. The knives aren’t sharp, but they do have a small toothed edge and they’re strong enough to cut through cakes and pie shells.