Preheat the oven to 325°F (163°C).

In a saucepan over medium heat, combine sugar and water, swirling the pan gently until the sugar dissolves and turns into a deep amber caramel.

Quickly pour the caramel into a round 9-inch baking dish, tilting to coat the bottom evenly.

In a mixing bowl, whisk together sweetened condensed milk, coconut milk, whole milk, eggs, egg yolks, and vanilla extract until smooth.

Strain the mixture through a fine sieve to ensure a silky texture.

Pour the custard mixture over the caramel layer in the baking dish.

Place the dish in a larger baking pan and fill the outer pan with hot water until it reaches halfway up the sides of the flan dish.

Bake for 50-60 minutes or until the flan is set but slightly jiggly in the center.

Remove from the oven and let it cool to room temperature, then refrigerate for at least 4 hours or overnight.

To serve, run a knife around the edges of the flan and invert it onto a serving plate.