Kentucky is only a stone’s throw away from Tennessee. The two states kiss along our northern border. So it’s no surprise that next to our own distilled whiskey — one step away from moonshine — the favorite hard liquor around these parts is bourbon.
Place the sugar in a bowl and add the vanilla seeds scraped from the bean with the tip of a sharp knife, the cardamom, cinnamon, and lemon zest; rub together with your fingertips to blend evenly. Add the peach slices and lemon juice and toss gently to coat. Let the peaches macerate at room temperature for at least 20 minutes.
To assemble the shortcakes, cut the pound cake into slices about ¾ inch thick. Place a slice on each of 8 dessert plates. Moisten the cake with some of the juices from the bowl of peaches. Top with a scoop of ice cream. Spoon the peach slices and remaining juices around the cake. Using a small pitcher, drizzle the caramel sauce over the ice cream and peaches in a thin stream. Garnish each shortcake with a sprig of mint.
Preheat the oven to 325 degrees. Grease a 9 by 5 by 3-inch loaf pan, line the bottom with parchment paper, and grease the paper.
In a mixing bowl, cream the butter until soft and fluffy. Beat in the brown sugar and vanilla. Continue mixing on medium speed until thoroughly blended. Add the whole eggs and egg yolks one at a time. Mix in each completely and scrape the bowl before adding the next one. Continue to beat on medium speed until light and fluffy.
Sift the cake flour directly over the butter mixture. Start to fold it in with a few strokes, then sprinkle the buttermilk evenly over the batter. Finish folding together until blended. Pour the batter into the pan.
Bake for 55 to 60 minutes, or until a toothpick or cake tester inserted into the center comes out clean. Let cool in the pan for 10 minutes, then turn out, peel off the paper, and let cool completely on a rack.
In a small saucepan, combine the cream, butter, and cinnamon stick. Scrape the seeds from the vanilla bean into the pan using the tip of a knife and toss in the pod. Set over low heat to warm the cream, melt the butter, and infuse the flavors, about 3 minutes.
In a separate deep saucepan, combine the sugar, corn syrup, and ¼ cup water. Bring to a boil over medium-low heat, stirring to melt the sugar. Using a moist brush, wash any sugar crystals off the sides of the pan. Continue to boil without stirring until the sugar syrup begins to color. Once it turns golden, gently swirl the pan and watch it closely. As soon as the caramel turns an even amber shade, remove from the heat.
Carefully pour a few tablespoons of the warm cream into the caramel; the mixture will boil up furiously. Whisk until smooth. Slowly whisk in the remaining cream. Continue to whisk until all the caramel is dissolved. Stir in the bourbon, remove the vanilla pod, and let the sauce cool to room temperature before serving.