(Nutrition information is calculated using an ingredient database and should be considered an estimate.)
Refrigerate cans of coconut cream overnight (do not shake).
Prepare jelly following packet directions. Pour into a 14cm-deep, 20cm round (16-cup-capacity) trifle bowl. Cover with plastic wrap. Refrigerate for 2 hours or until just beginning to set (mixture should have a thick, syrupy consistency). Stir in strawberries and raspberries. Cover. Refrigerate for 4 hours or until set.
Meanwhile, scoop the thick top layer of coconut cream from each can and place in a bowl (about 2/3 cup from each can). Cover with plastic wrap. Refrigerate.
Place remaining coconut cream (about 4 cups) in a large saucepan over low heat. Bring to a simmer. Remove from heat. Using an electric mixer, beat egg yolks, cornflour, 2/3 cup sugar and 2 teaspoons vanilla in a bowl until thick and creamy. Gradually whisk in hot coconut cream. Return to saucepan. Cook, stirring constantly, over medium-low heat for 4 to 5 minutes or until thickened. Transfer custard to a large heatproof bowl. Cover surface with plastic wrap. Refrigerate for 4 hours or until cold.
Meanwhile, make Vanilla Buttercake: Preheat oven to 180C/160C fan-forced. Grease a 6cm-deep, 22cm round cake pan. Line base and side with baking paper. Using an electric mixer, beat Flora, sugar and vanilla for 5 minutes or until light and fluffy. Add eggs, 1 at a time, beating until just combined after each addition. Add flour and milk, in 2 batches, beating until just combined after each addition. Spoon mixture into prepared pan. Level top with a spatula. Bake for 40 to 45 minutes or until a skewer inserted into the centre of cake comes out clean. Stand in pan for 10 minutes. Turn out, top-side up, onto a wire rack lined with baking paper. Cool completely.
Spoon 1/2 the custard over jelly. Spread to level. Level top of cake. Trim edge of cake to fit snugly into trifle bowl. Split horizontally. Sandwich together with jam. Place cake over custard. Drizzle with cranberry and raspberry juice. Whisk remaining custard until smooth. Spoon over cake. Cover with plastic wrap. Refrigerate overnight.
Using an electric mixer, beat reserved coconut cream with remaining sugar and vanilla for 2 to 3 minutes or until soft peaks form. Spoon coconut mixture over custard. Top with toasted coconut and extra strawberries and raspberries. Serve.