Asklemmy

Deep fry them

The internal heat is causing them to open up so you have to cook the exterior faster than the inside and frying is the only medium that's immediately hot enough to cook the outside before the inside and keep its temperature consistent when you add in the sticks.

I'm theory a hot enough convection oven should do the trick as well but it needs to be high quality enough (aka expensive) to recover the lost heat instantaneously.

This is one reason why I don't do mozz sticks until I have a fryer of some kind. Having worked in plenty of kitchens with deep fryers, they're the only/best way to eat fried foods.

Generally, once the cheese becomes liquid they're over cooked...

Mozz sticks are not a "set it and forget it" item and cooking conditions are different everywhere. Sticks also go from hot, to gooey mess very quickly.

You need to watch them, at least until you learn exactly how long to cook them in your oven.

One option is to try cooking them low and slow. Reduce the cooking temp and go for longer. This will take some trial and error.

Another option is to poke them part way through, before they split, to give steam a way to get out.

Finally, try keeping a close eye on them. When one splits, take them out before the rest follow, they're done.

I've been having this trouble with frozen burritos and what works for me is dunking them in water and putting them in an air fryer

Quickly dip them in the sun (or any G-type star). The high heat will immediately carbonize the outside keeping the mozzarella contained (and also carbonized).

Try higher heat with shorter time. Also preheat the oven first.

It might work better if you deep-fried them.

No, seriously: that way, they can cook quickly enough to get crispy before the water in the cheese has a chance to boil.

Are you using low moisture mozzarella?

Are you lancing them once? Cheese has a ton of water in it so you need to keep going until the stick cries out "Et tu Brutus?"

It's unavoidable - once the cheese gets hot enough the steam will either force the liquid cheese out of existing holes, or it will make its own holes.

Make sure they are fresh out of the freezer when you put them in, as this lets the outside crisp up more before the inside becomes lava. Once you get close to the prescribed cooking time, you need to just sit in front of the oven door and watch them, and as soon as 2-3 break open, take the whole tray out

That’s how you know they’re done

Have you tried mixing in a 1/4 cup of non-toxic glue?

That's actually what i would have suggested as a first.

Are you cooking them on the flat of the pan, or are you using a baking rack in the pan? They tend to do better on a rack from what little I've done them.