FOR CRUMBS: Mix all ingredients in a small bowl till crumbly.
Press into a 9" square pan and bake at 375° for about 15 minutes or till golden brown.
Crumble while hot and set aside. Cool completely.
FOR FILLING: Beat cream in a large bowl till peaks form. Beat in the vanilla. Set aside.
In a large mixing bowl beat cream cheese till creamy and smooth. Gradually beat in the sweetened condensed milk. Blend well. Fold in the whipped cream.
TO ASSEMBLE: Set aside about 1/2 cup of the crumb topping.
Divide half of the remaining crumb mixture between 12 small mason jars. Add a few banana slices to each jar. Add half of the cream mixture to the jars.
Repeat the crumb, banana, and filling layers in each jar. Sprinkle the reserved crumbs over the top. If desired, garnish with a banana slice right before serving.
Notes
Serve immediately or chill for up to 2 hours. (Not much longer or the bananas turn brown.)