1. Start by greasing a 9"x13" baking dish or lining it with parchment paper. This ensures that your cake doesn’t stick and comes out beautifully. Set it aside so it's ready for the batter.
2. In a measuring cup, combine milk, warm water, and a dash of sugar. Stir gently to mix, then sprinkle the active dry yeast over the surface. Allow it to sit for about 5 minutes until it becomes foamy. This is a crucial step, as it activates the yeast, which will help your cake rise.
3. While waiting for the yeast to activate, preheat your oven to 220 degrees F. This step is optional, but it can help reduce rising time, making the process quicker.
4. In the meantime, cream unsalted butter, granulated sugar, and salt in a large mixing bowl using a stand mixer. Beat on medium speed until the mixture is light and fluffy, which takes about 2 minutes. This creates a wonderful base for your cake.
5. Add the large egg to the mixture and mix well until fully incorporated.
6. Now, gradually add the all-purpose flour alternating with the yeast mixture. Mix until a smooth dough forms. The dough should be sticky but not wet, meaning it won’t pull away from the sides of the bowl.
7. Transfer the dough into the prepared baking dish. Using your hands, gently pat it down to cover the entire bottom of the dish. It may take a while, so be patient and keep pressing until it's evenly spread.
8. Cover the dish with a kitchen towel and place it in a warm, draft-free area to rise for 2 to 3 hours. Alternatively, you can place it in the preheated but turned-off oven for about 30 minutes. This rising step is essential for achieving that light, fluffy texture.
9. Once the base has risen, take it out of the oven and preheat your oven to 350 degrees F. This is the perfect temperature for baking your cake.
10. In a small measuring cup or bowl, mix together light corn syrup, water, and vanilla extract. Set this mixture aside for later.
11. In another large mixing bowl, beat unsalted butter for about 20 seconds. Gradually add granulated sugar and cream them together until light and fluffy. Be sure to scrape down the sides of the bowl as needed.
12. Mix in the additional large egg until well blended.
13. Now, add all-purpose flour alternating with the corn syrup mixture. Beat everything together until smooth and creamy.
14. Drop dollops of the filling over the cake base and spread it with a spatula to smooth out the top. It’s okay if it looks a bit rustic; that’s part of its charm!
15. Bake in the preheated oven for 25 to 30 minutes or until the top is golden brown and the filling is gooey. The fragrance of the baking cake will fill your kitchen with an irresistible aroma.
16. Once done, let the cake cool in the pan. This allows the filling to set up a bit.
17. Before serving, dust the top with powdered sugar for an elegant finishing touch.
