Good deniability though.
Be publicly into micology and commonly collect mushrooms to cook when you have guests over.
Only issue would be to somehow plausably not poison yourself to death. Maybe taking little enough you survive.

And take care you aren’t quite known as fully competent, spread the air of knowledge without any solid proof or association.
I’ll look like you were a sham and amateur overestimating themselves.

Or just accidentally run them over with a car.