Preheat oven to 350°F (175°C). Grease and flour a 9×13-inch baking pan or line with parchment.

In a large bowl, whisk 3 large eggs with 1/2 cup sugar until pale and slightly thickened.

Add 3 tbsp softened margarine (or melted butter) and 1 cup coconut milk. Mix until combined.

Stir in 2.5 cups all-purpose flour gradually until you have a smooth batter. Don’t overmix — stop when no dry streaks remain.

Pour batter into prepared pan and smooth the top. Bake for 30–40 minutes, or until a toothpick inserted into the center comes out with just a few moist crumbs.

When the cake is done, remove from oven but keep it in the pan. Let it rest for 5 minutes.

While the cake bakes, combine 1 can sweetened condensed milk, 1 can evaporated milk, 1 cup coconut milk, and 2 tbsp sugar in a saucepan. Warm gently until the sugar dissolves and the mix is hot but not boiling — stir frequently.

Poke the hot cake all over with a fork or skewer (1/2-inch apart). Slowly pour the warm milk mixture over the cake, allowing it to sink in.

Immediately sprinkle 1 cup shredded coconut over the surface. Cool to room temperature, then refrigerate for at least 1–2 hours to set and chill before slicing.