Instructions
1 In a medium saucepan place rhubarb, sugar, zest and juice, and 2 tablespoons water. Cover and bring to boil over high heat. Reduce heat to low and simmer for 8-10 minutes until rhubarb is soft and most of the liquid reduced. Pour off excess liquid and set aside.
2 In a small saucepan gently heat the milk over medium heat until just starting to bubble around the edges, but don’t let it boil. Remove from heat and set aside. Meanwhile, in a small bowl combine egg yolks, sugar and cornflour and beat with an electric mixer until pale and thick. Add vanilla extract and whisk to combine. Gradually add heated milk, a little at a time, whisking well to combine. Return mixture to milk saucepan and set over a medium-low heat (lower if your stove runs hot). Cook, stirring with a wooden spoon, for 10-15 minutes until thickened. Set aside to cool slightly.
3 Preheat oven to 180°C. Lightly spray six medium muffin tin holes (approx ¹⁄³ cup capacity) with oil then line the bottoms with baking paper. Lay out one pastry sheet and using a sharp knife, cut into six even pieces. Line one of the muffin tin holes with a pastry square. Gently press in until it fits snugly and cut away excess pastry with a sharp knife, leaving a ½cm overhang. Repeat with remaining pastry squares.
4 Pour custard into each pie case to ¼ full. Top custard with stewed rhubarb. Carefully place a lattice round (see HFG tip) on top of each pie and gently press edges together to seal. Trim any untidy edges with a sharp knife. With a pastry brush, lightly brush tops with egg white. Sprinkle with cinnamon sugar if using.
5 Place pies in oven and bake for 25-30 minutes until golden. Allow to cool slightly before removing from muffin cases. Serve warm with remaining custard.