Ivan, this example makes no sense to me. Having Cooker, MealCooker and MealHandler just makes things more confused than simpler.

I understand how to use Lower Bound, but not when, and as the post makes explicit, when to use it is not as common as the Upper Bound and I was fine with that.

There is also the fact that contravariant parameters are a very complex case to understand and I didn't want to address them in this post.