Melted butter, to grease
8 mandarins, peeled (reserve five peels, see Cook’s tip below)
200g almond meal
1 tsp baking powder
300g caster sugar
2 Tbsp black chia seeds
Candied mandarin strips, to garnish (see Cook’s tip below)
Double cream, to serve
Cook tip: To garnish cake with candied mandarin strips, use a sharp knife to remove all pith from inside of reserved mandarin peel. Put in a bowl, cover with boiling water and stand for 5 minutes to soften. Drain, then shred into fine strips. Put 1 cup caster sugar and 1 cup water into a small saucepan over a medium heat and cook, stirring, until sugar dissolves and mixture comes to the boil. Reduce heat to low, add shredded rind and cook for a further 20 minutes or until mixture is syrupy and rind is transparent. Remove from heat, and cool.
Preheat oven to 180°C. Grease a round 20cm springform cake tin and line base and sides with baking paper. Put 3 mandarins in a medium saucepan with enough water to cover. Place a small plate on top to keep fruit submerged, then cook on a medium heat for 30 minutes or until softened. Drain mandarins crossways and allow to cool slightly. Halve mandarins crossways and remove seeds. Put in the bowl of a food processor and puree until smooth. Transfer to a large bowl.
Beat almond meal, baking powder, eggs and 1/2 of the sugar into the mandarin puree using a wooden spoon. Spoon mixture into prepared cake tin, smooth top, then bake for 30–35 minutes or until cooked when tested with a skewer. Cool in tin, then transfer to a cake stand or serving plate.
Meanwhile, to make syrup, cut remaining mandarins in half and juice. Scoop out pulp and discard, but keep mandarin peels to make the candied mandarin strips (see Cook’s tip). Put 1 1/2 cups mandarin juice and remaining sugar in a small saucepan over a medium heat and cook, stirring, until sugar dissolves and mixture comes to the boil. Reduce heat to low and simmer for 8 minutes or until mixture becomes syrupy. Mix through chia seeds, then remove from heat and stand for 20 minutes. Strain through a fine sieve over a small bowl, and set aside seeds and syrup.
Spoon syrup over cake, then cut the cake into pieces and place a small pile of the chia seeds and candied mandarin on top of each slice. Serve with double cream and extra mandarin peel on the side.