Preheat your oven to 350°F (175°C).

Melt the granulated sugar in a saucepan over medium heat to create caramel, stirring constantly until it becomes an even amber color.

Quickly pour the caramel into a round cake pan, evenly coating the bottom.

In a large bowl, combine sweetened condensed milk, coconut milk, eggs, and vanilla extract. Whisk until smooth.

Pour the custard mixture over the caramel in the cake pan.

Place the cake pan in a larger baking dish, then add hot water to the baking dish until it reaches halfway up the sides of the cake pan.

Bake in the preheated oven for 1 hour or until the flan is set and a knife inserted comes out clean.

Allow the flan to cool at room temperature, then refrigerate for at least 4 hours before serving.

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