300ml pouring cream
1 vanilla pod, seeds only
1 strip orange zest, pith removed
4 egg yolks
75g caster sugar
500g rhubarb, trimmed and cut into 8cm pieces
2/3 cup sugar
5 leaves gelatin
1 tbsp Grand Marnier, plus extra for sprinkling
1 store-bought panettone, cut into a 16cm circle 3cm high
300ml double cream
For custard, warm cream, milk, vanilla seeds, and zest in a saucepan. Whisk yolks in a bowl with sugar until pale and fluffy. Slowly add milk mixture; whisk until combined. Return custard to a fresh pot and cook over low heat, stirring, until custard thickens. Pour into a bowl; refrigerate.
For jelly, place rhubarb and sugar in a saucepan with 500ml water. Bring to the boil; stir until sugar dissolves. Reduce heat; simmer for 6-8 minutes. Strain liquid into a bowl. Place rhubarb in a separate bowl; refrigerate. Soak gelatin in cold water until softened. Squeeze out excess water; add gelatin to rhubarb liquid along with Grand Marnier. Stir until gelatin dissolves, pour jelly into an 8-cup-capacity trifle dish, and refrigerate until set.
Top jelly with panettone; sprinkle with extra Grand Marnier. Spoon over rhubarb compote, pour over custard, and top with double cream.