Preheat oven to 350 degrees F.
In a large pot of seasoned water, cook the pasta to al dente, and drain well.
Heat the vegetable oil in the skillet. Add ground beef and diced onions, and cook until the beef is no longer pink and the onions soften. Drain excess grease if necessary.
While the beef and onions are cooking, prepare the hot dog “fingers”. Score and remove a square shape on one end of each hot dog to sculpt a fingernail, and using a knife, make shallow cuts to resemble knuckles. Set aside.
Once the ground beef is fully cooked, add spaghetti sauce, Rotel, cream of chicken soup, Worcestershire sauce, and taco seasoning to the skillet. Mix well.
Add cooked spaghetti and shredded pepper jack cheese to the meat mixture and toss until well combined. Transfer to a casserole or baking dish.
Randomly place the hot dog “fingers” into the spaghetti.
Cover with foil. Bake in a 350-degree oven for 20-25 minutes until the spaghetti is heated through.
While the spaghetti is baking, prepare the olive “eyes” and “spiders”. Slice a few olives to create circles. These will be placed on the mozzarella pearls to look like eyeballs. Then, slice several of the olives lengthwise-these will be placed on the sliced mozzarella and create the shape the “spider” bodies.Using the remaining olive halves, cut eight “legs” for each of the spiders.
Take the casserole out of the oven and discard foil. Evenly place the sliced, fresh mozzarella andscatter the mozzarella pearls over the top of the spaghetti..Return the entire dish to the oven, uncovered, and bake for 2-3 minutes or until the mozzarella begins to melt.
Remove the casserole from the oven, and working quickly, assemble the “eyeballs” onto the mozzarella pearls and the “spiders” onto the sliced mozzarella.
Serve and enjoy!