Sticky clementine & tarragon cake

Preheat the oven to 160ºC, gas mark 3. Grease and line the base and sides of a 20cm springform cake tin with baking parchment. In a large bowl, use your fingers to rub the sugar, clementine zest and tarragon together, then add the butter and use an electric hand mixer to beat until pale and creamy (4-5 minutes). Add the eggs, one at a time, beating well after each addition. In a separate bowl, mix together the ground almonds, polenta, baking powder and a big pinch of salt, then gently fold into the cake batter until everything is combined. Spoon the mixture into the cake tin and bake for 40-45 minutes until golden brown and a skewer inserted comes out clean. Cool the cake in the tin for 20 minutes, then carefully turn out onto a plate or cake platter.

While the cake is cooling in the tin, put all the syrup ingredients in a saucepan. Simmer over a medium-low heat for about 10 minutes, or until reduced and thickened slightly, then set aside to cool until just warm to the touch. Discard the tarragon sprigs. Once the cake is out of the tin, prick it all over with a skewer, then generously spoon ¾ of the syrup over the top. Serve the cake, still warm or allow to cool completely, with the extra syrup and some crème fraîche, if liked.