Upside down orange & chocolate cake

I really wanted to make a chocolate & blood orange cake, but unfortunately the blood oranges I bought turned out to be classic oranges! It doesn't matter, choco-orange is also very good, so here is a simple recipe that will delight you if you like this association
 
 
 
 Prep time : 15 minutes
 Cooking time : 20 + 30 minutes
 For a 26cm cake | 8 servings :

 

Ingredients :

 2 oranges
 400g water
 200g sugar
 
 90g softened butter
 120g sugar
 The zests of one orange
 3 eggs
 50g orange juice
 100g dark chocolate
 170g flour
 4g baking powder
 65g liquid cream
 
 

Recipe :

 Bring the water and sugar to a boil. Cut the oranges into half centimeter thick slices.
 
 
 
 Put the slices in the syrup and let them cook for 20 minutes at low temperature. Then drain them, blot them with paper towels and let them cool. 
 Melt the chocolate. 
 Mix the butter with the sugar and the zests.
 
 
 
 Add the eggs one by one, whisking between each addition. Add the orange juice and then the melted chocolate.
 
 
 
 
 Stir in the sifted flour and baking powder, then add the cream.
 
 
 
 Butter a 26cm diameter cake tin, and put a circle of greaseproof paper at the bottom of the tin to make it easier to unmould.
 
 
 
 Butter the parchment paper, then sprinkle the sugar over the entire surface of the pan. Arrange the orange slices, then cover with the cake batter.
 
 
 
 
 Bake in the preheated oven at 180°C for 30 minutes (a knife should come out dry). 
 Unmold immediately, then let cool before enjoying!