Spoon 1/4 cup of the dulce de leche into a microwave-safe bowl. Microwave on HIGH for 15 seconds.
Stir, then pour the dulce de leche into the prepared graham cracker crust and spread to a thin layer.
Next, slice two of the bananas and arrange the slices over the dulce de leche; set aside.
Pour the whipping cream into the bowl of a stand mixer fitted with the whisk attachment.
Beat until stiff peaks form.
Fold in 1/2 cup of the remaining dulce de leche.
Chop the last banana into the mixture and add the toffee bits; fold in.
Pour into the crust and spread to an even layer.
Freeze for at least 6 hours, or until frozen solid.
When ready to serve, let the pie set out for 10-15 minutes to thaw out a bit. Then, the pie is ready to enjoy in all of its creamy, flavorful glory! :)