Preheat oven to 350 degrees. Spray a 9" x 13" baking dish with non-stick cooking spray and set aside.
Bring a large pot of water to a boil. Stir in 1/2 TBS salt and 8 oz uncooked spaghetti. Cook per directions on back of package for al dente. Drain spaghetti and leave in pot.
In a large skillet over medium high heat break up ground beef and brown until no longer pink. Drain excess grease. Stir in chicken broth and taco seasoning.
Mix in canned diced tomatoes with juice, rotel tomatoes, and cream of chicken soup. Let simmer 3 minutes.
Place sliced velvetta cheese from a block in a single layer on top of the mixture. Stir until melted.
Add in cooked & drained spaghetti and stir until well combined. Pour spaghetti mixture into prepared baking dish and smooth evenly.
Sprinkle cheese all over mixture. Place in preheated 350 degree oven and bake for 25-30 minutes until cheese has melted.
Sprinkle green onions on top for a garnish. Let cool for a few minutes before serving.
