Superfun 21 ...
... is the game you're describing. House edge is a huge .94% off the top IF you know Superfun strategy, which is different from "normal" blackjack. If you don't know this strategy thoroughy, don't play this game. Without knowing the strategy, the house edge is even worse.
Superfun 21 is beatable, but only under certain conditions that are tough to find, and usually don't last very long.
Also, be careful to avoid the "single deck blackjack pays 6 to 5" ploppy ripoff game that has reared it's ugly head at Station Casinos in recent weeks. Total scam and ripoff, DO NOT PLAY.