Preheat oven to 180°C/356°F (conventional heat). Line the bottom of a 10"/26cm or 9"/24cm springform pan with parchment paper and grease the sides with butter.
In a clean bowl, whisk egg whites with a pinch of salt using a hand or stand mixer until stiff peaks form. Set aside in the fridge.
1 pinch salt , 6 eggs
In a separate large bowl, cream together butter, sugar, egg yolks, and milk until light and fluffy. Mix in vanilla and almond extracts. Add flour, baking powder, and ground almonds, mixing until just combined. Pour in the melted chocolate and gently fold until the batter is smooth.
Carefully fold the chilled egg whites into the chocolate batter in two additions. Mix gently until just combined—overmixing will deflate the whites and create a dense cake.
Pour or spread the cake batter in the form.
Peel and core all 4 pears. Quarter 2 pears and set aside for the top decoration. Quarter the remaining 2 pears, then chop them into 3cm bite-sized pieces for the filling.
4 pears
Spread one-quarter of the batter in your prepared pan. Evenly distribute the chopped pear pieces over the batter. Pour the remaining batter on top, spreading gently. Finally, arrange the pear quarters in a circular pattern on top with the rounded sides facing up. Don't press them down—the batter will rise around them naturally.
Bake for 40-45 minutes (10" pan) or 55-60 minutes (9" pan). The cake is done when a skewer inserted in the center comes out clean or with just a few moist crumbs.
Let the cake cool completely in the pan before removing. Dust with powdered sugar just before serving.
Video
Notes
Which pears to use: Use pears that hold their shape when being baked. Conference Pears, Anjou, William, or Bosc Pears are ideal. How to melt the chocolate: You can melt the chocolate in short 30-second intervals in a microwave-safe bowl while stirring in between. Alternatively, you can melt it using a double boiler or a heatproof bowl over simmering water. Continue stirring to avoid burning.