Stick a cast iron or other heat proof skillet into your Pit Boss grill and preheat to 400°F.
In a blender or food processor, add milk, eggs, flour, cinnamon, and white sugar. Blend until smooth.
Once the grill has preheated, add 4 tablespoons of butter to the pan and swirl it around to coat until all butter is melted. Pour the batter into the pan and grill for 20 minutes, then reduce the temperature to 300F and grill for an additional 5-7 minutes, until the dutch baby is golden and puffy. Remove from the grill and serve immediately before the dutch baby deflates.
In a large saute pan, heat the remaining butter over medium heat and add the apple slices. Cook for 5 minutes until the mixture begins to thicken slightly. Add the brown sugar and bourbon and cook until saucy. Top the dutch baby with the apples and serve.