Method

• To begin, preheat the oven to 180C/160C fan/gas 4. Take a 2lb loaf tin, measuring 22 x 10cm and 6cm deep, and spread butter all around the tin. Afterward, line it with baking parchment.Next, take a large bowl and place the butter, dates, and bicarbonate of soda. The bicarbonate of soda helps to break down the dates. Pour 150ml of boiling water over the ingredients, give it a stir so that the butter melts, and then leave it to stand for around 20 minutes until the dates become soft.
• After 20 minutes, add the sugar to the bowl and whisk it until it becomes smooth. Then, gradually add in the eggs and whisk until they are fully combined. Beat in the baking powder, flour, and a pinch of sea salt. Continue whisking until the mixture becomes smooth and there are no lumps of flour left.Take three-quarters of the walnuts and fold them into the mixture. Once that's done, pour the mixture into the prepared tin. Sprinkle the remaining walnuts over the top of the mixture.
• Place the tin into the preheated oven and bake it for 20 minutes. After that, reduce the oven temperature to 170C/150C fan/gas 3 and continue baking for another 45-50 minutes, or until the cake becomes golden brown and a skewer inserted into the center comes out clean.When the cake is done, let it cool in the tin for 15 minutes before transferring it onto a cooling rack. Once it is on the rack, let it cool completely. When it is fully cooled, lightly dust it with icing sugar and serve it in slices.