Bring 200 g (1 cup) granulated sugar to heat without stirring, gently swirl the pan as it caramelizes
Pour caramel into bundt pan (do not grease) and swirl around, set aside to cool
Mix all flan ingredients together in a bowl, whisking gently to avoid incorporating too much air
Mix box cake in a separate bowl, substituting ½ cup brewed coffee and ½ cup heavy cream for water, and cooled melted butter for oil
Layer the cake mix on top of the caramel in the bundt pan
Strain the flan mixture over the cake mix
Cover tightly with tin foil and place in a water bath with very hot water
Bake at 325°F for 75 minutes
Let the chocoflan come to room temperature for around 2 hours
Refrigerate for minimum 2 hours or overnight
Run a knife along the sides and center to loosen and flip onto a serving plate
