In a one gallon zip lock bag, put your graham crackers, ritz crackers, and brown sugar. Press all the air out, zip it up and on a counter carefully with a rolling pin crushed cracker mixture finely.
Pour crust mixture in a 13x9-inch square dish. Melt your butter in a bowl in the microwave and pour slowly over dry crust mixture. blend crust ingredients well and pat down firmly with your clean hand or a fork.
In a mixer bowl pour 2 3/4 cups of milk and 2 packages of dream whip powder, let it mix about 2 or 3 minutes, then add your two packages of chocolate pudding and mix until very thick and creamy. Spoon carefully over crust mixture and spread slowly to edge of pan.
After you had washed and dried the mixer bowl and beater (I used wire whisk attachment) place your other 1 cup of milk and vanilla along with 2 other packages of dream whip powder in your bowl. Mix until thick about 5 minutes. Then add your jif into the mixture. Blend until well combined. Spoon out dollops of the topping all around the top of the filling and carefully spread to edges. Refrigerate 2 hours or until ready to serve. Yum!