To make a 20cm (8in) round cake:
- 3 clementines (about 250g)
- 175 golden caster sugar
- 4 large eggs
- zest from one large lemon and juice separately
- 175g fine ground hazelnuts
- 25g polenta
- 90g (100ml) olive oil
- 2 tsp baking powder
- Heat your oven to 180C and grease a 20cm/8in spring-form cake tin and line the bottom with baking paper.
- Place the clementines in a saucepan and just cover with water. Bring to the boil and simmer gently for 20–25 minutes until tender. Remove and set aside until cool enough to handle. Cut the clementines in half and discard any pips.
- Put the clementines, including the skin, into a food processor and blend to a paste.
- Whisk together the eggs, lemon zest and 160g of the caster sugar in a bowl. Add the olive oil and beat until light and well combined. Stir in the clementine paste then fold in the ground hazelnuts, polenta and baking powder.
- Pour the mixture into the tin and bake for 50 minutes or until well risen and golden-brown. The cake should have slightly shrunken from the sides and be springy to the touch. Leave it to cool in the tin on a wire rack.
- To make the syrup, warm the remaining sugar and lemon juice in a small pan over a low heat until the sugar has dissolved. Make lots of small holes all over the cake with a cocktail stick, and drizzle over the lemon syrup. Let the cake cool completely, turn it out on to a serving plate and dust with icing sugar.
Serve with creme fraiche and orange segments … or just plain