Hello Lisa P. My apologies that you had a tough time with this recipes. The idea behind the thickening of the mixture is the when acid in the lime juice reacts with the proteins in the milk which will create a thicken custard mixture that can be spooned out and spread. It is important to whisk in the ingredients in the order stated in the direction where the lime juice is the last ingredient added. I hope this helps. Thanks , Chef Ashley

This was an awesome recipe! Came out perfect. Recommend making this in the blender and mixing the cream cheese evaporated milk and condensed milk first and adding lime juice slowly, a little at a time thickens much better this way!