In a mixing bowl, combine ground almonds, oat flour, and cornflour. Add maple syrup and melted coconut oil, mixing until uniform. Press into tart cases and poke holes to prevent bubbling.

Preheat oven to 350°F (175°C) and bake crusts for 15-20 minutes until lightly golden. Cool completely on a wire rack.

Thaw raspberries in a saucepan over low heat, then use a sieve to separate juice from seeds. Blend raspberry puree with drained cashews until smooth, then combine with maple syrup, cornflour, and melted coconut oil in the saucepan and heat until thickened.

Pour the thickened raspberry curd into cooled tart shells and refrigerate for at least 4 hours to set.

Whip aquafaba in a clean bowl until soft peaks form, then gradually add powdered sugar and whip until stiff peaks. Top tarts with meringue and toast lightly.