In a cup, combine boiling water and espresso powder until dissolved, allow to cool
Cover the bottom of a 2 quart rectangular dish with hall of the cake cubes; drizzle with 1/2 cup of the espresso. Spoon 1 cup pudding over the top in an even layer. Spread 1 cup whipped topping over the pudding.
Top with remaining cake cubes, drizzle with remaining espresso. Spread remaining pudding over the top and then top with remaining whipped topping and sprinkle with toffee bits.