Firecracker and it’s not even close. I’ve put ice cubes up there before and it wasn’t nearly as bad as you’d imagine. The shape of it will make it easy. Plus, the ridges on it mean you’ll have less ice in contact with your skin. At some point it melts and it’s just a Popsicle stick.

Edit: Additional thoughts on this because I can’t stop thinking about how goofy this is lol. I’ve cream sandwich and to a lesser degree the chipwich are tempting. The difficulty would be that they just crumble and don’t really go in, but you have to shove it in. I’m counting melted ice cream/ice that comes out after it’s in as not needing to be reinserted. I’ve cream sandwich “crust” is actually very soft so it wouldn’t be bad to have in there. It’s just the process of getting it in would be very weirdly difficult.

Many of the other choices (like the snow cone thing and push pop) have a lot of plastic parts that make it basically impossible.

The drumstick may seem tempting but it’s just gonna crack and hurt.

Once the popsicle stick of the firecracker is in, you just softly pull it out. The biggest risk is splinters, but I don’t think popsicle sticks in popsicles ever really have splinters like the loose ones you can buy for projects.