Wash the pineapple thoroughly. Carefully peel the pineapple, keeping the peels as intact as possible. You can also include the core for extra flavor.

In a large glass jar or food-grade bucket (at least 3-liter capacity), combine the pineapple peels, piloncillo (or brown sugar), cinnamon stick, and cloves (if using).

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

Cover the jar opening with a cheesecloth or a clean kitchen towel, securing it with a rubber band. This allows air circulation while keeping out contaminants.

Place the jar in a warm spot (ideally 70-80°F / 21-27°C) away from direct sunlight. Let it ferment for 2-4 days.

Check the tepache daily. You'll start to see small bubbles forming on the surface, and it will develop a slightly sweet, tangy, and yeasty aroma. A thin white film (kahm yeast) might form, which is normal; skim it off if desired. Discard immediately if you see any signs of colorful mold.

Once the desired flavor and fizziness are achieved (usually after 2-4 days), strain the liquid through a fine-mesh sieve into clean bottles or jars. Discard the pineapple peels and spices.

Cap the bottles tightly and refrigerate. Tepache will continue to ferment slowly in the refrigerator, so consume within a week for best flavor and carbonation.