Roast the coconut in a coated pan without fat until golden brown, remove. Coarsely chop the nuts. Peel bananas, weigh 450 g of flesh. Mash with a fork. Mix banana puree, sugar, eggs and buttermilk with the stirrers of the hand mixer until creamy. Mix flour, baking powder and 1 pinch of salt, sieve over it and stir in. Fold in nuts and coconut
Fill the dough into a greased box form (approx. 25 cm long; approx. 1.5 l capacity) and smooth it down. Bake in a preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: see manufacturer) for 35-45 minutes, remove from oven. Leave to cool in the tin for approx. 10 minutes, turn out onto a cake rack and let it cool down completely
For the sashimi, cut off 8 thin slices of bread (use the rest of the bread for other purposes). Cut out or cut slices of bread as circles as you like. Heat oil in a large frying pan. Fry the slices of bread on each side until crispy brown. Take out and let it drip off on kitchen paper
Cut the mango from the stone, peel 1/2 mango, dice the flesh. Use the remaining mango for other purposes. Remove the avocado flesh. Dice avocado and tuna finely and mix loosely with the mango cubes. Mix soy sauce, 5 tbsp. water, chilli sauce, sesame oil and lime juice and drizzle over the mixture. Arrange the sashimi immediately on the crostini and serve garnished with the roe
waiting time approx. 2 hours