Step 1: Obtaining Mesophilic Culture.
Where do we obtain our raw Gram-positive bacteria you ask? Well, we go where S.L. poops and spits; Cultured Buttermilk, a dive bar where all the bacterium of the Lactis likes to hang. Make sure your cultured buttermilk from your local grocery store has live cultures and hasn't been euthanized via pasteurization. We need live specimen.
Step 2: JAR the SUCKERS in a Warm Spot.
24hrs later and the lactic acid bacteria should have increased acidity, the by-product naturally produced by S.L. while fermenting lactose, the primary sugar found in milk. As lactic acid is produced by the bacteria, the pH of the milk decreases and casein, the primary protein in milk, precipitates causing the curdling or clabbering of milk. This process makes buttermilk thicker than plain milk.