Toss potato slices with 2 tbsp olive oil and season with salt and pepper. Place on a parchment lined sheet pan and roast until tender, about 7-9 minutes.
While potatoes are roasting, combine alfredo and sour cream together. Set aside.
Now cut the potatoes into fun and spooky shapes. For example, ghosts, jack-o-lanterns or fangs/teeth. You can use Halloween cookie cutters. Use the black olives for eyes on the ghosts or jack-o-lanterns or to create small spiders.
Roll out your pizza dough to about ¼” to ½” with some flour to your desired shape.
Brush pizza skin with 1 tbsp olive oil. Now spread the alfredo-sour cream sauce in a thin layer on the pizza shell, leaving a ½” space on the edge for the pizza crust.
Sprinkle the cheddar cheese onto the sauce and then top the cheese with the bacon bits, green onions, red onions and finish with potatoes.
Place the pizza in the oven and cook for 8-12 minutes. Cook until golden brown and crispy. Remove from the oven, let cool for 3-4 minutes, cut and enjoy!