Grease a six-cup Texas muffin pan. Line bases of the pan’s cups with baking paper.

Melt butter and chocolate together in a saucepan over a low-medium heat, stirring until smooth and well-combined. Transfer to a large bowl.

Beat egg yolks, eggs and sugar in a small bowl with an electric mixer until thick and creamy.

Fold egg mixture and flour into chocolate mixture. Spoon mixture into pan cups and refrigerate for at least 3 hours.

Peel oranges and slice into 1cm pieces. Bring ¼ cup water, sugar and lemon juice to a boil. Simmer for 5 minutes, then add Grand Marnier. Remove from heat, immediately add orange slices and leave to cool.

Preheat oven to 180°C.

Place the muffin pan filled with fondant mixture on an oven tray. Bake for 14 minutes. Stand fondants for 3 minutes and then use a small spatula to lever them out of the pan and onto plates.

Dust cocoa powder on top and serve immediately with oranges and a little of the poaching liquid.