Preheat grill for medium high heat.
Wash, dry and slice sweet potatoes, dice onion and jalapeno. Add olive oil to cast iron skillet, making sure all edges are coated. Begin layering sweet potatoes on the outer edges, overlapping over the previous slice in a circular pattern, until you have completely filled the outer and inner spaces. Add onions, jalapenos on top and season with salt.
Place skillet on the grill and cook for 10 minutes. Next, add the baked beans. Cook for 2-3 minutes. Combine pulled pork with apple juice and place on top of beans. Cook for another 10-12 minutes until the potatoes have cooked through and the beans and pulled pork are good and hot.
Using heat resistant gloves, carefully remove skillet from the grill. Set aside.
Prepare the sauce mixture by combining buttermilk with barbecue sauce. You can place the sauce in a condiment bottle to make application easier. Drizzle sauce over the top of the nachos, and then top with coleslaw. Serve.
If you'd like cheese on the nachos, do so while it's still on the grill. Just place it right on top of the pork. I recommend pepper jack, smoked gouda, white cheddar, or cotija cheese.