Preheat the oven to 350F. Grease 3 8-inch round cake pans and line the bottoms with parchment paper. Dust the sides of the pan with flour, tapping out any excess.
Whisk together the oil, granulated sugar, brown sugar, eggs, ginger and zest.
In a separate bowl, sift the flour, baking powder, cinnamon, cloves, allspice, and nutmeg. Add this to the oil mixture and stir until blended (or use electric beaters or a stand mixer).
In another bowl, whisk the molasses, maple syrup, ginger beer (or ale), lemon juice and baking soda (this will froth up). Add this to the batter and beat vigorously until smooth – the batter will be very fluid. Pour the batter into the prepared pans and bake for about 30 minutes, until a tester inserted in the centre of the cake comes out clean. Cool the cakes for 30 minutes in their tins, then turn out to cool completely.
For the icing, beat the butter with half of the icing sugar and the lemon zest. Add the lemon juice, water and vanilla and beat in. Add the remaining icing sugar and beat well, until the icing is fluffy and spreadable.
To assemble, place one cake layer on a platter and spread the top with a third of the icing. Dot the icing with raspberries and place a second cake layer on top, pressing down gently. Spread another third of the icing over this layer and dot with raspberries. Top this with the final cake layer, spread the remaining icing overtop and garnish with the remaining raspberries. Chill the cake until ready to serve.
The cake will keep, refrigerated, for up to 3 days.