Crushed Frosted Flakes cereal mixed with peanut butter. Make a ball about as big as a golf ball and put it in the trap. Works every time.

I use the Duke's dog free traps, and can't use baits like that in them. I've found fish flavored dry cat food works really good as a bait for them. It also handles rain better without becoming a mush as fast as some baits. I keep an empty milk jug full of it in my truck and it's easy to transport and pour into the traps.

I use marsh mellows with my dog proof traps, one under the trigger then set one on top. If they eat the freebie on top they go for the one in the trap and get caught.

I use bait shrimp. If I used any type of cat food or grain I would catch a lot of rats. With the shrimp I catch a lot of coons.

Dukes traps baited with mini marshmallows / fruit loops has worked well for us.

The coons are coming to the feeder to get corn, so we use corn in DP traps. Heck a coon will demolish a feeder to get corn.
During the great acorn drop a few years back we had an inch of corn on the ground. Coons are so curious that they would still get caught in the DP trap.
We are well over 400 coons on corn alone. It is easier, it is right there in the feeder, just drop some in the DP trap. Some baits tend to attract ants and turn to mush in the rain.
I really believe that anything that sounds like munchies will catch a coon.

Marshmallows is all you need