The right way to say it would simply be "Bitcoin", but we can't call it that currently because so few understand that Bitcoin can even be defined by anything other than popular demand or even full node miner support. So instead we call it Bitcoin Cash.
BCash on the other hand is a Brazilian owned company and payment system that has nothing to do with Bitcoin. That's why a few high ranking r/Bitcoin redditors fueled what has spread to be a social media spam campaign to call Bitcoin Cash "BCash", so that users will be confused.
The people controlling r/Bitcoin and BitcoinTalk since Satoshi left are no longer aligned with his vision of scaling the main chain without requiring 3rd party intermediaries. As they don't allow other opinions there, you should use r/btc instead, which was started for the purpose of not banning based merely dissenting views.