What can you do to mitigate that fear? You obviously know there’s some irrationality to it, but that doesn’t mean that it would be invalid to try and dampen some of those concerns ^^
How about getting a little fire extinguisher for your kitchen? I’m confident with cooking, but I still always have one on hand just in case!
You can also try and experiment with what exactly your boundaries are. Are you comfortable making something like a soup/stew? Does it bother you to bake something? That might be more than enough for the start, and once you get comfortable with that you might even naturally want to level up to scarier stuff.
When it comes to fears, the only way to lose is not to try. Because every instance of avoiding something you’re afraid of reinforces that fear by making you think that you successfully avoided a scary situation. Even if absolutely nothing would have happened otherwise.
Good luck!
There are some Lemmy clients where you can block specific keywords, communities and instances.