In a small bowl, combine red onions, green onions, Jalapeño pepper, tomatoes, salt to taste. Set aside.
In a large skillet, brown meat and drain grease. Add taco seasoning and stir.
In a medium pot, bring heavy cream and butter to a boil, stirring until thickened. Remove from heat and add 2 cups of cheese. Add Cajun seasoning and keep warm.
In 9 x 13 casserole, layer 4 tortillas (cut so they fit in bottom of casserole), ground beef, cheese, and tomato mixture. Repeating until you have 3 layers finishing with the cheese sauce on top.
Add last cup of cheese on top of entire casserole.
Place in 400 degree oven covered for 20 minutes then remove and let cool. Garnish each serving with sour cream and green onions. Say Grace and enjoy!