Add the water, salt, brown sugar, black peppercorns, thyme, sage, rosemary, bay leaves, and garlic to a pot.
1½ gallons water, 2¼ cups kosher salt, 1 cup brown sugar, 1 tablespoon whole black peppercorns, 1 bunch fresh thyme, 1 bunch fresh sage, 3 sprigs fresh rosemary, 3 bay leaves, 1 head garlic