Bring the double cream and milk to a boil in a saucepan.
Whisk egg yolks and caster sugar in a bowl before pouring in the hot liquid.
Cook mixture on low heat until it reaches 82°C, then add fir sprig and boil.
Let custard infuse and cool for one hour before straining through a fine sieve.
Cover surface with plastic wrap and chill in the fridge.
Combine orange zest, juice, butter, and sugar in a heatproof bowl over simmering water.
Beat in eggs and whisk until thickened, then cool completely.
Preheat oven to 180°C and line a tray with parchment.
Melt butter and set aside to cool while remaining runny.
Process coconut until fine and blend with icing sugar, flour, egg whites, and butter.
Spread teaspoons of paste into 7cm circles on the tray.
Bake for seven minutes until golden and shape over a rolling pin while warm.
Plate orange curd, top with whipped custard, and garnish with tuilles.