01 -
Preheat oven to 175°C and grease a 23 cm springform pan.
02 -
Heat milk until just below boiling. Whisk egg yolks and sugar until pale, then gradually combine with warm milk. Return mixture to low heat and cook, stirring constantly until thickened. Strain and chill custard.
03 -
Mix cold butter, flour, sugar, and oats until crumbly. Chill streusel until firm.
04 -
Beat butter and sugar until light and fluffy, then incorporate eggs one at a time.
05 -
Sift flour, baking powder, cinnamon, and salt. Fold into creamed mixture alternating with milk or cream until fully integrated.
06 -
Spread batter evenly in the prepared pan, arrange apple slices on top, then scatter streusel over the apples. Bake for 50 to 60 minutes, until golden and a skewer inserted comes out clean.
07 -
Allow cake to cool slightly, remove from pan, dust with confectioner’s sugar, and serve.