Preheat your oven to 160°C (320°F) and prepare a pudding mold or small bundt pan.
Make the caramel: in a small heavy saucepan combine Granulated Sugar and Water over medium heat; let the sugar dissolve and then gently simmer without stirring, swirling the pan occasionally until the syrup turns a deep amber. Carefully pour the hot caramel into the bottom of the mold and tilt to coat the base and a little of the sides; set aside to harden.
Prepare the custard: in a mixing bowl, lightly whisk the Eggs until homogeneous, then add the Sweetened Condensed Milk and the Whole Milk. Whisk until smooth and well combined.
For an extra-silky texture, strain the custard mixture through a fine sieve into a pouring jug to remove any foam or egg strands.
Pour the strained custard over the set caramel in the mold. Place the filled mold into a larger baking pan and pour hot water into the outer pan to create a bain-marie that comes about halfway up the sides of the mold.
Bake at 160°C (320°F) for about 45–60 minutes, or until the custard is set at the edges and still slightly wobbly in the center. Cooking time will vary with mold size and oven.
Remove the mold from the water bath and let it cool to room temperature, then refrigerate for at least 4 hours or preferably overnight to fully set and develop flavor.
To unmold, run a thin knife around the edge of the pudding, briefly dip the bottom of the mold in hot water to loosen the caramel, then invert onto a serving plate so the caramel flows over the top. Serve chilled.
