Wash the pineapple thoroughly. Remove the crown and base, then peel the skin, keeping the peels and core. Cut the remaining pineapple flesh for another use, or chop some small pieces to add to the tepache.

In a large, clean glass jar or pitcher (at least 1-gallon capacity), combine the pineapple peels, core, piloncillo (or brown sugar), cinnamon stick, and cloves.

Pour the filtered water over the ingredients, ensuring everything is submerged. Stir well until the sugar dissolves.

Cover the jar with a cheesecloth or a clean kitchen towel and secure it with a rubber band. This allows air to circulate while keeping out contaminants.

Place the jar in a warm spot, away from direct sunlight, to ferment for 24-72 hours. The warmer the temperature, the faster it will ferment.

Check the tepache daily. You'll start to see small bubbles forming on the surface and a foamy layer. Taste it after 24 hours; it should be slightly fizzy and sweet.

Once it reaches your desired level of fizziness and tartness (typically 2-3 days), strain the liquid through a fine-mesh sieve into clean bottles or jars. Discard the solids.

Store the finished tepache in the refrigerator. It can be consumed immediately but tastes best chilled. Enjoy plain or over ice.