01 -
Preheat oven to 180°C. Grease a 23 cm round cake pan thoroughly to prevent sticking.
02 -
In a small saucepan, melt 28 g butter and 67 g sugar over low heat until dissolved. Pour the caramel evenly into the base of the prepared pan.
03 -
Place orange slices in a single, overlapping layer over the caramel layer, ensuring full coverage.
04 -
In a medium bowl, whisk together flour, baking powder, baking soda, and salt until fully blended.
05 -
In a separate large bowl, beat softened butter and sugar until pale and fluffy.
06 -
Beat in eggs one at a time, then blend in orange juice, zest, and vanilla extract until smooth.
07 -
Gradually fold the dry ingredient mixture into the wet ingredients, mixing until just combined. Do not overmix.
08 -
Gently pour batter over the arranged orange slices, spreading evenly with a spatula.
09 -
Bake on the center rack for 40 to 45 minutes, or until a toothpick inserted into the center emerges clean.
10 -
Allow to cool in the pan for 10 minutes. Run a knife around the edge, then carefully invert onto a serving plate. Serve warm or at room temperature.