Pre-heat your oven to 180°C. Line a square baking tin or tray (approx 20 x 20 x 5cm) with baking paper.
Beat the caster sugar and eggs together for five minutes, until pale and creamy.
Slowly pour in the oil and beat again. Add the almond extract and mix in well.
Grate in the zest of one lemon or orange.
Sift the flour and baking powder into the mixture and carefully mix (with a metal spoon, not mixer) until it is all combined.
Add in the ground almonds and carefully mix again. Pour in the cake batter. Scatter the halved cherries over the top and push down, leaving some of the cherries visible.
Bake in the pre-heated oven for 40-45 minutes, or until a toothpick comes out clean.
Dust with the icing sugar and cut into squares or slices. Serve warm or cool. Keeps well in a tin for up to five days.