|Remove label from can of sweetened condensed milk. Immerse unopened can in a deep pot or slow cooker filled with boiling water. Cover and simmer (slow cooker setting to high) for 3 hours; be sure to top up with water frequently during cooking, so can is always completely under water. If the pot is allowed to boil dry the can will explode. Remove the tin from the water and allow to cool completely before opening. The sweetened condensed milk becomes soft toffee.
|Preheat the oven to 350°F. Combine melted butter and graham cracker crumbs in a bowl. Press firmly onto bottom and up sides of a 9” pie plate or tart pan. Bake pie crust for 12 minutes and allow to cool. Pour the toffee over the graham cracker crust. Peel and halve the bananas lengthwise and lay them on the toffee.
|Whip cream until soft peaks form. Add powdered instant coffee and icing sugar. Continue whipping until stiff peaks form. Spoon whipped cream on top of the bananas. Grate chocolate over whipped cream topping. For best results when serving, freeze overnight and thaw in the fridge 4 hours before serving. The pie should be slightly frozen. Alternately, chill in the refrigerator for at least 2 hours or up to 1 day before serving.