Go to the options menu

set the KO count to 1

Keep it on the Medium Difficulty setting

Play as Mama Tua

Use her Forward, Forward+HR(High Right) punch to inflict heavy Damage to your opponents.

Setting the difficulty on Easy, triggers the Mama Tua fight at the end of the game, J.R. Flurry on Medium, and Joey T. on Hard difficulty.

You now finished the game in under 4 minutes.