Instructions:
- Preheat oven to 350°F (175°C). Grease a 9-inch round cake pan and line the bottom with parchment paper.
- In a medium bowl, whisk together the eggs and 1/4 cup of the powdered sugar until light and frothy.
- In a separate bowl, mix together the flour and remaining 1 cup of powdered sugar.
- Gradually add the flour mixture to the egg mixture, mixing until well combined.
- In a small saucepan, melt the butter over medium heat. Stir in the milk and water, and heat until just warm.
- Slowly pour the warm liquid into the egg mixture, whisking constantly.
- Pour the batter into the prepared cake pan and place the pan in a larger baking dish. Fill the larger dish with enough boiling water to reach halfway up the sides of the cake pan.
- Bake for 40 to 45 minutes, or until the cake is set and a toothpick inserted into the center comes out clean.
- Remove the cake pan from the water bath and let it cool completely. Dust the top with powdered sugar before serving.
