To make pickled green tomatoes, cut 2 pounds of green tomatoes into small wedges or 1/4-inch thick slices. Divide the tomatoes into thirds and pack them tightly into three half-pint jars. Also place a few dill fronds and garlic slices in each jar.
In a small saucepan over medium heat, combine 2 cups each of water and white vinegar. Also add 2 tablespoons of salt, 2 tablespoons of sugar, 1/2 teaspoon of red pepper flakes and 1 tablespoon of whole black peppercorns. Bring the liquid to a simmer and stir until the sugar is fully dissolved, then remove the pan from the heat and stir in 2 tablespoons of bourbon.
Pour the warm brine into the jars over the tomatoes. Fill the jars almost to the top, leaving only about 1/4-inch of room. Make sure the brine completely covers the tomatoes. If the tomatoes are not packed tightly enough and they start to float, put a few more in to make sure they stay submerged. Screw the lids tightly onto the jars and refrigerate for at least three days to allow the tomatoes to pickle. The pickled tomatoes stay good for up to two weeks when stored in the refrigerator.