In a large bowl mix together cream cheese, mayonnaise, and soup mix with a large spoon or electric mixer on low until well combined. Stir in spinach and one cup of Swiss cheese.
Spoon dip into an ungreased 9-inch pie plate. Spread dip to edges of the pie plate and to form an even layer. Sprinkle remaining one cup of Swiss cheese on top.
Bake dip for about 20 minutes at 375 degrees F or until heated through.
SNAPPY TIPS: Be sure the cream cheese is at room temperature and soft to prevent lumps. The dip can be made ahead of time, covered, and refrigerated for a few days. Let dip come to room temperature before baking.SNAPPY SUBSTITUTIONS: Instead of Swiss cheese, you could substitute your favorite shredded cheese. You can use low fat ingredients in this recipe, BUT the consistency and taste of the finished dish may vary a lot.