In a large bowl, combine the softened cream cheese, butter, powdered sugar and vanilla with a fork until the mixture is smooth. Use name brand cream cheese to avoid lumps.
Add the blackberries to the mixture, and mix them until they break apart a bit.
Fold in the whipped cream to the mixture, until there are no longer any white streaks.
Refrigerate the mixture for two hours before serving for best results.
Put your graham crackers into a gallon sized baggie and crush with a rolling pin.
In each solo cup, add first about a half inch of crushed graham cracker, then fill the cup with the blackberry cream cheese mixture, then top it with the spray whipped cream to garnish.