I don't know if this entirely counts as trashy eats, but it seems that ease-of-production fits in this community.
No-Bake cheesecake
1 pack cream cheese
1 can condensed milk (not to be mistaken for evaporated milk)
1/3 cup lemon juice
1 pre-made graham cracker crust
Let the cream cheese come to room temperature. Beat the cream cheese on high for 2-3 minutes or until completely whipped. Whip the condensed milk into the cream cheese. Finally whip in the lemon juice.
Pour into the pre-made crust and let sit in the fridge for a hour to let it set.
Goes well with fresh berries.
You can enhance it in several ways. You can whip in 2/3 of a cup of Nutella or 2 tbsp of instant mocha coffee powder to filling. I'd also recommend substituting the lemon juice for Frangelico, Crème de Cacao, or other chocolate friendly liqueur. You can also get a pre-made chocolate graham cracker crust.
Another option is to fold fresh blueberries into the filling before pouring it into the crust.
I've updated a few suggested measurements.