Preheat your oven to 350°F (175°C). Grease a 9-inch round cake pan and set aside.
In a large mixing bowl, whisk together the eggs and sugar until the mixture becomes pale and slightly fluffy, about 3–4 minutes. This introduces air to help the sponge rise.
Gently fold in the vanilla extract, then pour in the melted butter, mixing just until combined. This adds richness to the batter.
Sift the flour into the wet mixture to prevent lumps, then carefully fold it in using a spatula until just combined. Be gentle to maintain airiness.
Pour the batter into your prepared cake pan and smooth the top with a spatula. Bake for about 25–30 minutes, or until the cake is golden brown and a toothpick inserted in the center comes out clean.
Remove the cake from the oven and let it cool in the pan on a wire rack for 10 minutes, then transfer it out of the pan to cool completely.
Once cooled, pierce the surface of the cake several times with a fork to create holes that will absorb the milk mixture.
In a bowl, whisk together the sweetened condensed milk, evaporated milk, and heavy cream. Pour this mixture evenly over the cake, allowing it to soak in.
Cover the cake and refrigerate for at least 4 hours, or overnight, to let the milk soak fully into the sponge, resulting in a moist and creamy texture.
Before serving, optionally top the cake with whipped cream and slices of fresh fruit for added flavor and presentation.
Slice and serve the tres leches cake chilled, enjoying its luscious, milk-soaked sponge and soft, creamy topping.
