Grease and line a 20cm round cake tin. Preheat oven to 160’C.
Mix the ground almonds, golden caster sugar, breadcrumbs and baking powder together in a bowl. Whisk the eggs, sunflower oil and zest of the orange together and add to the almond mixture. Pour into the tin, increase temperature to 180’C and cook for 1 hour.
Meanwhile make the candied lemon slices. Place the water and sugar in a saucepan, over a medium heat and stir until the sugar is dissolved. Bring to the boil and simmer the syrup for 2 mins. Add the lemon slices and orange juice and simmer for 10 mins until lemons are translucent and the syrup has thickened.
Pierce the top of the cake with a skewer several times and pour over the citrus syrup. Leave to cool completely.
To Serve:Serve with a dollop of freshly whipped cream.