Preheat oven to 350 degrees F.
In a large skillet, heat the oil over medium heat. Add the beef and cook, breaking up any large chunks, until beef is browned and no pink remains (7-8 min). Sprinkle with 1 ½ Tablespoons taco seasoning and stir thoroughly to combine. Remove from heat and set aside.
In a medium bowl, beat together the cream cheese, sour cream, and and remaining teaspoon of taco seasoning until combined.
In a 9 x 13 inch baking dish, layer ground beef, cream cheese mixture, and salsa. Top with shredded cheese.
Bake for 20-25 minutes or until cheese is melted and bubbly.
Serve plain, or top with lettuce, tomatoes, red onions, and green onions. Serve with tortilla chips.