Divide beet chunks between 2 clean 1-quart jars with lids. Add 2 cloves garlic, 3 peppercorns, and 1 bay leaf to each jar.

Stir water and salt together in a bowl until salt is completely dissolved. Pour enough brine into the jars to completely cover the beets.

Screw on lids and let jars sit at room temperature until foam starts to appear on top, about 1 week. Transfer jars to a cool place (50 degrees F (10 degrees C)) for 2 to 3 days after foam appears. Store in the refrigerator.