For almond cream, preheat oven to 160C. Scatter almonds on an oven tray and roast until light golden (8-10 minutes). Meanwhile, bring milk and sugar to the boil in a saucepan over medium-high heat, add almonds, remove from heat, cool slightly, then blend in a blender until smooth. Refrigerate for flavours to infuse (4 hours-overnight), then strain through a muslin-lined sieve, pressing on solids to extract liquid (discard solids). Add cream and crème fraîche, whisk until smooth, refrigerate until required.
For crème fraîche pastry, process flour, butter, sugar and a pinch of salt in a food processor until fine crumbs form. Add crème fraîche, rind, vanilla seeds and 1 tbsp chilled water and pulse until dough comes together. Form one-third of pastry into a disc, form remaining pastry into another disc, wrap separately in plastic wrap and refrigerate until chilled (30 minutes).
Preheat oven to 180C. Roll out larger piece of pastry to a 32cm-diameter round, then line a pie tin with a 22cm-diameter base and a 28cm-diameter top. Roll out remaining pastry to a 29cm-diameter round, cut a small hole in centre and transfer to a tray. Refrigerate both pieces of pastry to rest (30 minutes). Blind bake base until golden around the edges (10-15 minutes), remove paper and weights and continue to bake, gently pressing pastry occasionally with a clean cloth to prevent rising, until light golden (5-10 minutes), then scatter with almond meal.
Meanwhile, combine peaches, sugar, lemon juice and reserved vanilla bean in a bowl and stand to macerate (20 minutes). Strain juice from peaches into a small saucepan, bring to the boil over medium-high heat and cook until reduced to a thick syrup (5-10 minutes). Meanwhile, add cornflour to peaches and toss to combine. Add ¼ cup peach syrup to peaches (reserve remainder to serve) and toss to coat.
Transfer peach mixture to pie dish. Brush edges with eggwash, top with remaining pastry, press gently to seal, then trim edges. Brush with eggwash, scatter generously with sugar and bake until golden (25-35 minutes). Serve warm or at room temperature with chilled almond cream, extra peach syrup and maple syrup.