Preheat your oven to 350°F (175°C) and prepare your baking dish.

In a mixing bowl, crack large eggs and beat them until frothy (about 2-3 minutes).

Incorporate coconut milk, palm sugar, salt, and vanilla extract into the beaten eggs and whisk until smooth.

Strain the mixture through a fine sieve into another bowl.

If adding sticky rice, spread it evenly across the bottom of your prepared baking dish.

Pour the strained custard mixture over the sticky rice or directly into the dish.

Place the baking dish into a larger pan filled with hot water to create a water bath.

Bake in the preheated oven for approximately 45 minutes to 1 hour.

Once baked, let it cool to room temperature on a wire rack, then transfer to the refrigerator to chill for at least 2 hours.

Slice the custard into squares with a hot knife and garnish with fresh mango, toasted coconut flakes, or coconut sorbet before serving.