Step 1

Preheat oven to 180°C. Grease a baking tray and line with baking paper.

Step 2

Place the pumpkin, cinnamon, nutmeg, oil and a pinch of sea salt on prepared tray and toss to coat. Roast for 60 minutes or until pumpkin is cooked through and beginning to caramelise. Set aside for 10 minutes to cool slightly, then place in a food processor with yoghurt and whiz until smooth. Transfer to a bowl and chill.

Step 3

Grease a 20cm baking pan and line the base and sides with baking paper.

Step 4

Place butter and demerara sugar in a stand mixer fitted with the paddle attachment and beat on high until thick and pale. Fold through almond meal. Transfer 1 cup to pan, pressing in to create a base.

Step 5

Combine pumpkin yoghurt, baking powder, rosewater, vanilla and eggs with remaining almond meal mixture, then pour over base and sprinkle with half the pistachio.

Step 6

Bake for 1 hour 15 minutes or until a skewer inserted in the centre comes out clean. Cool completely in pan, then remove from pan and chill.

Step 7

Combine icing sugar and 2 1/2 tbs water in a bowl until smooth. Pour over cake and top with remaining pistachio to serve.