Place the sugar and water in a sauce pan and stir until the sugar dissolves. Slowly heat over high heat until the syrup boils. Allow it to boil until the color begins to brown. Swirl the pan only if the caramel appears to be browning unevenly.

Divide the caramel between 6 ramekins.

Preheat the oven to 325°F.

In a separate bowl whisk together the egg yolks, Z-sweet and vanilla extract until smooth.

Place the water in a separate sauce pan or tea pot over high heat.

Place the milk in a sauce pan over medium-high heat and bring to a boil whisking frequently.

The moment the milk begins to boil remove it from the heat and slowly drizzle into the egg mixture whisking continuously.

When all of the milk is well blended into the egg mixture ladle the custard into the ramekins. Place the filled ramekins in a shallow roasting pan. Fill the pan with the hot water until it is about half way up the sides of the ramekins.

Place the water bath with the ramekins in the preheated oven and cook for 35 minutes.

Remove the custards from the water bath and allow them to cool. Cover with plastic wrap and chill in the refrigerator for at least 4 hours.

To serve gently run a knife around the outer edge of the caramel. Place a plate upside down on top of the ramekin and invert the flan onto the plate.

Serve.