Prepare the Oven and Tin: Set your oven to 150°C (300°F) or 130°C (fan). Lightly grease a 900g (2 lb) loaf pan and line it with parchment paper.

Prepare the Butter Mixture: In a medium saucepan, combine the butter, sugar, water, raisins, sultanas, currants, and mixed peel. Heat gently over medium-low heat, stirring occasionally, until the butter has melted and the sugar is dissolved. Remove from heat and allow to cool for about 10 minutes.

Mix Dry Ingredients: In a large bowl, sift together the self-raising flour, mixed spice, and bicarbonate of soda.

Combine Wet and Dry Ingredients: Gradually add the cooled butter and fruit mixture into the dry ingredients. Stir gently until just combined.

Add the Eggs: Beat the eggs lightly and fold them into the batter until fully incorporated. Be careful not to overmix.

Bake: Pour the batter into the prepared loaf tin, smoothing the top with a spatula. Bake in the preheated oven for 1 hour 45 minutes to 2 hours, or until a skewer inserted into the center comes out clean.

Cool and Serve: Let the cake cool in the tin for 10 minutes before transferring it to a wire rack to cool completely. Slice and serve with tea or coffee for a cozy treat.