Heat oven to 160°C / 140°C (fan oven) / 320°F / Gas Mark 3. Butter and line the base of a loaf tin with baking parchment. Tip the flour and spice into a food processor and add the butter. Whizz to make fine crumbs, then mix in the sugar. Tip into a mixing bowl and stir in the raisins, eggs, apples and milk. Mix well until everything is evenly combined, then spoon into the prepared tin and smooth the top.
To make the topping, rub the flour, butter and sugar through your fingers to make a rough crumble, then stir in the nuts. Sprinkle evenly over the cake mixture and bake for 50-55 mins, until firm to the touch and a fine skewer inserted into the centre comes out clean. Cool in the tin for 15 mins, then turn out and cool on a wire rack.