Firstly, I've abandoned the method of growing mushrooms known as the "PF Tek Method". The yield from the jars of spawn took eternity (2-3 months) to colonize. Plus, they produced a very small amount of spawn.
The method that I've been using with success is the" drink-coffee-in-the- morning-feed-the-Oyster-Mushroom-Spawn-the-grounds-at-night" method. I'll call it the "Slow Coffee-drinker's Method". Observe my fully-colonized jars below. Within days, the new coffee grounds become overtaken with mycelium.
Some people say that the jars need to be dunked in water and left overnight in the fridge (24 hours) to promote fruiting.
Some people say "don't bother".
I tend to favor peoples' ideas when they are simpler. But, I've decided to perform an experiment. I'll "dunk" one and not the other. Stay tuned for the results!
My "fruiting chamber" idea is just to partially cover the mouth of the jar with plastic and mist it daily (mushroom-kit style). I make sure that some of the jar is exposed to light, while the bulk of it isn't, as it occurs in nature.