Grease a box mould (26 cm long) and sprinkle with sugar. Coarsely chop the nuts. Mix eggs, 100 g sugar and 100 g butter with the whisk of the hand mixer for about 3 minutes
Peel the bananas, weigh 300 g of fruit flesh, crush and fold into the dough. Mix flour, baking powder, salt and cinnamon and stir in briefly, alternating with the milk. Fold in 125 g nuts. Fill the dough into the form, smooth it down
Bake in a preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: see manufacturer) for approx. 1 1/4 hours. Cover with aluminium foil after about 30 minutes. Take the cake out of the oven, place it on a cake rack and let it cool in the tin for about 20 minutes. Loosen the rim with a knife and turn out of the tin. Let it cool down
For the toffee mass, caramelise 50 g sugar in a pot until brown. In the meantime, cut 125 g butter into small cubes, add to the caramel with cream, boil down for 10-15 minutes while stirring (check if the toffee becomes firm!)
Pour the toffee mixture into a large bowl and allow to cool for about 15 minutes. (If the toffee mixture is too firm, bring to the boil again with a little cream, if it is too soft, boil it down again for a few minutes while stirring). Pour the sauce over the cake, sprinkle with the remaining nuts and chill until the caramel is a little firmer
waiting time approx. 2 hours