Preheat oven to 350 degrees F. Grease and flour two 9-inch cake rounds and set aside.
To Make the Pound Cake:
Cream together the butter and sugar until light and fluffy, about 5 minutes. Add the eggs one at a time, mixing well after each addition. Stir in the vanilla extract.
In a separate bowl, whisk or sift together the flour baking soda and salt. Add to the butter mixture and stir until just combined. Stir in the sour cream. Divide the batter evenly among the prepared cake pans and gave them a few taps on the counter to dislodge any air bubbles. Bake until golden brown and a toothpick inserted in the middle comes out clean, about 18 to 22 minutes. Remove from the oven and let cool completely.
To Make the Peach Jam Layer:
In a large bowl, stir together the preserves, peaches, and bourbon if using. Cover with plastic wrap and store in the fridge until ready to use.
To Make the Cobbler Biscuit Pieces:
In a large bowl, combine the flour, baking soda, and salt. Add in the cold butter and work with your hands or a pastry blender until the butter resembles coarse crumbs. Gently stir in the buttermilk with a wooden spoon until the mixture comes together. Using a small ice cream scoop, scoop out the batter onto two baking sheets lined with parchment paper. Brush with melted butter on top and sprinkle with granulated sugar. Bake until golden brown, about 12 to 15 minutes. Remove from the oven and let cool completely.
To Assemble the Peach Ice Cream Layers:
Allow the vanilla ice cream to soften a bit. Then transfer to a large bowl. Fold in the peaches and preserves gently, until streaked throughout the vanilla ice cream. Pour into a 9-inch round cake pan that has been lined with plastic wrap. Press the peach ice cream down into a smooth even layer. Cover with plastic wrap and freeze until firm, about 4 hours. Pour the softened peach sorbet into a 9-inch round cake pan that has been lined with plastic wrap. Press down into a smooth even layer. Cover with plastic wrap and freeze until firm, about 4 hours.
To Make the Caramel:
Place the sugar and water in a medium saucepan, set over medium-high heat. Gently swirl the pan constantly, without actually stirring the mixture, and cook until it becomes a dark amber color. Remove the saucepan from the heat and slowly whisk in the heavy cream. It’ll bubble up and get thick, but keep stirring until smooth. Whisk in the bourbon vanilla bean seeds and salt. Pour into a jar and allow to cool down to room temperature. Once cool, store in the fridge until ready to use.
To Assemble the Cake:
Line the sides of a 9-inch springform pan with parchment paper, to create high sides. Trim the top of the cooled pound cake layers to even them out. Place one layer of pound cake, upside down, into the spring-form pan. Pour half of the peach jam over the cake layer and spread out evenly. Freeze until firm, about 1 hour. Crumble a few of the biscuits and sprinkle them evenly over the jam layer. Carefully remove the peach ice cream from the cake pan and remove the plastic wrap. Place into the spring form pan on top of the cobbler layer. Then place the second pound cake layer inches Pour the remaining peach jam over the cake and spread out evenly. Chill in the fridge until firm, about 1 hour. Top with more crumbled cobbler biscuits and then finally the peach sorbet layer. Freeze once more until firm, about 3 hours.
To Make the Butter Cream:
Beat the butter until light and fluffy about 5 minutes. Add in the powdered sugar, a cup at a time, beating well after each addition. Add in the milk, vanilla extract and salt. Beat on high until creamy and smooth. Divide the buttercream into 3 separate bowls. Dye one a dark orange. One a lighter orange and then leave one white. Transfer each to disposable piping bags.
Remove the cake from the freezer and then carefully remove it from the springform pan, discarding the parchment paper from the sides. Starting from the bottom of the cake, pipe out two rows of dark orange buttercream all around the cake. Then pipe out two rows of the lighter orange buttercream around the cake, and then pipe out 2 rows of white buttercream around the sides and top of the cake. Pipe out light orange buttercream on the top center of the cake.
Using an offset spatula or a bench scraper, smooth out the buttercream on the sides and bottom. Coat the bottom of the cake with crumbled cobbler biscuits. Return to the freezer while you prepare the topping.
To Grill the Peaches:
Place a stovetop grill pan over medium-high heat, once hot, grease with canola oil and place the peach halves on top, cut side down. Cook for about 1 to 2 minutes or until grill marks form. Transfer to a cutting board and let cool down completely. Slice them in half, leaving two intact.
To Decorate the Top of the Cake:
Drizzle the edges of the cake with the caramel sauce so that it drips down the sides. Then arrange the grilled peaches on top along with some crumbled cobbler biscuit pieces. Cut and serve immediately or place in freezer until ready to serve.