Place the pork shoulder in the slow cooker and coat with barbecue sauce. Cook on low for about 8-9 hours or on high for about 4-5 hours. When done, you should be able to pull the pork apart easily.
Coat the steak in avocado oil and sprinkle with salt and pepper. Melt butter. With the grill on medium high, cook the steak to an internal 135 degrees and cook the corn until charred. Baste the corn with butter as it cooks to help it char. Once done, cube the steak and cut the corn kernels off the ear of corn.
Spread the tortilla chips evenly on the sheet pan. Cover the chips in cheese. Add the steak and pork to the top of the nachos. Place the nachos in the broiler for about 5 minutes to melt the cheese. If you do not have a broiler, bake at 350 degrees for about 10 minutes or until the cheese melts.
Spread mild salsa, the corn, and cubed avocado on top of the nachos. Drizzle with sour cream. Serve immediately.