In a large mixing bowl, beat cream cheese and sugar until light and fluffy. Fold in whipped topping with a rubber spatula and spread into an even layer over the crust. Be sure to spread the cream cheese mixture all the way to each corner to prevent the gelatin layer from seeping through. Cover and refrigerate.
Meanwhile, in a clean, large bowl mix the boiling water and gelatin for two minutes until dissolved. Add the pineapple with its juice and the drained mandarin oranges, stirring to combine. Cover and refrigerate until no longer hot or slightly set, about 30-60 minutes.
When gelatin has cooled, carefully pour over cream cheese layer and spread the fruit into an even layer. Cover and chill until completely set, about 2-4 hours. Before serving, cut into squares, garnish with extra whipped topping and a pretzel, if desired.
Do not substitute fresh pineapple for canned, or the jello will not set.
Baking the pretzel crust comes down to personal preference. We don't typically bake ours with this recipe, but you can absolutely bake it at 350F for 10 minutes before adding the rest of the layers. Be sure to let it cool before adding the cream cheese layer! Baking the crust will help make your slices neater, but it isn't mandatory.
If you aren't a fan of pineapple, you can simply omit it However, you do need to drain the mandarin oranges and add an extra cup of boiling water if you decide to omit the pineapple and its juice. Feel free to use extra mandarin oranges if desired. The crushed pineapple adds lots of flavor and pairs really well with the oranges!