Place the evaporated milk in a medium saucepan. Using a sharp paring knife, split the vanilla bean lengthwise and scrape the seeds from the vanilla bean using the back of the knife to prevent the pod from breaking.

Add the seeds and bean to the saucepan. (If any of the vanilla seeds get stuck to your fingers, grab some sugar and rub the sugar between your fingers over the saucepan to remove every last bit of vanilla seeds and let fall into the cream.

Whisk over medium heat until the mixture comes to a simmer. Cover the pan, reduce the heat to low, and simmer for 10 minutes. Strain into a large measuring cup or bowl with a spout and either discard the vanilla bean or reserve, dry out and add to your sugar bowl! Let it cool.

In a medium saucepan over medium heat, add 1 cup of sugar. Cook the sugar, stirring occasionally until it begins to melt and turns brown around the edges. Use a heatproof rubber spatula to pull the melted sugar around the edges toward the center of the unmelted sugar; this will help the sugar melt evenly.

Continue cooking and pulling the melted sugar until all the sugar is melted and the caramel is uniformly dark amber (it should smell caramelly but not burnt), about 10 to 12 minutes total. (If you still have undissolved lumps of sugar, stir it off the heat until melted.)

Next, carefully pour the room-temperature water into the melted sugar while continuously stirring the mixture with a heatproof rubber spatula tilted slightly to prevent hot steam from burning you. The mixture will bubble and steam vigorously, and some of the sugar may harden up and crystallize, but don't worry; just keep stirring the mixture over medium heat for an additional 1-2 minutes until the sugar re-melts completely and the caramel is smooth.

Be careful not to overcook the caramel, as it can burn quickly and become bitter.  Pour the caramel into the bottom of (8) 9oz Ramekins; quickly swirl around to coat all bottom and sides. Lay a dishtowel on the bottom of a roasting pan, place the ramekins on top of the towel, and set aside to cool completely.

Combine the condensed milk, eggs, pure vanilla extract, and evaporated milk and vanilla bean mixture in a blender or food processor and purée until smooth but not too frothy.

Pour the egg-based custard base through a fine-mesh strainer into a clean bowl to ensure a silky smooth texture. Divide the custard equally between your caramel-coated dish or ramekins.

Adjust a rack to the middle position and preheat the oven to 350° degrees. Bring water to a boil in a kettle. Transfer the flan to the oven, and fill the roasting pan with water to the halfway point. Bake until just set, about 35 to 45 minutes; the finished flan should have a slight jiggle in the center. Don't worry if it seems undercooked; it will continue to cook as it cools.

Next, remove from the oven and allow the ramekins to cool in the water bath for 1 hour. Then, remove from the water bath and let the flan cool completely before serving, either at room temperature or in the refrigerator, for about 4 hours.

When ready to serve, remove the flan from the refrigerator and let it sit for 10 minutes.  Next, fill a shallow pan with hot water. Dip the bottom of the ramekin in hot water for a minute before inverting it so the caramel loosens from the bottom of the ramekin.

Run a knife around the ramekin's rim, and be sure to reach the caramel on the bottom; tilt the ramekin slightly to allow a bit of the caramel into the gap.