I make it in a coffee pot - remember those?
You put the ground coffee in the pot, pour on boiling water, stir, let stand for a few minutes, and if the grounds are at the top, just stroke the surface with a spoon and they sink down leaving clear coffee - no need for a strainer, let alone a plunger.
And don't put cognac, etc. in it. It spoils the coffee, and besides the cognac tastes better on its own.