Prep. Wash jars with hot, soapy water. Transfer the clean jars to a water bath canner. Fill the canner and the jars with water so that the jars are fully submerged. Place over medium heat. Place the lids and rings in a saucepan over low heat and allow to simmer. Bring a separate pot of water to a boil.
Prepare and boil cherries. Rinse, stem, and pit cherries. Transfer them to the pot of boiling water and boil for 3 minutes. Transfer them to a mesh strainer and drain them.
Dissolve sugar. Add the sugar, water, lemon juice, and the split vanilla bean in a medium-sized pot. Bring to a boil and dissolve the sugar.
Add cherries. Once the sugar is dissolved, add the cherries. Reduce the heat to a simmer, and cook the cherries at 180℉ for 5 minutes.
Add bourbon. Remove from the heat and add the bourbon and almond extract. Stir to combine.
Remove vanilla bean. Remove the vanilla bean from the cherry mixture.
Fill. Remove the jars from the canner and place a canning funnel over one jar. Transfer the cherries to the hot jars, leaving ½ inch headspace. Using a debubbler tool, remove any bubbles. Refill the jars to maintain a ½ inch headspace. Wipe the rims of the jars with a clean, moist towel. You can use a towel moistened with white vinegar.
Process. Place the lid and rings on the jars and transfer them to the water bath canner. Make sure that the jars are fully submerged in water, with at least 2 inches of water covering the jars. Set the heat to medium and cover the water bath canner with the lid. Bring the water to a full rolling boil. Once boiling, set a timer for 10 minutes.
Cool. After 10 minutes, remove the canner from the heat, remove the lid, and allow the jars to sit for 5 minutes. After 5 minutes, transfer the jars to a heat-safe area and let them cool for 12-24 hours.
Check seals. After 24 hours, check the lids for a proper seal. If a proper seal has been confirmed, remove the rings, label the jars, and store the jars in a cool, dark area for 12-18 months or per your lid manufacturer’s recommendations.