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.

Carefully pour the caramel into the bottom of (8) 9 oz Ramekins; quickly swirl around to coat all bottom and sides. The caramel hardens as it cools, so work quickly. Let the caramel cool completely.

Adjust a rack to the middle position and preheat the oven to 350° degrees. Put the evaporated milk in a saucepan and bring it to a simmer over medium heat for about 5 to 6 minutes. Remove from heat and add the chocolate and cover, and let soften for about five minutes. Whisk until the chocolate is melted and smooth. Let it cool off a bit.

Place all the remaining flan ingredients in a large bowl; whisk everything until completely smooth and evenly combined. Pour in the milk/chocolate mixture, and again, whisk everything until completely smooth and evenly combined.

Pass the mixture through a fine strainer into a large measuring cup to ensure that the flan will be perfectly smooth. Slowly pour into the caramel-coated ramekins to avoid air bubbles.

Lay a dishtowel on the bottom of a roasting pan, place the ramekin on top of the towel, and then fill the pan with boiling water about halfway up the sides of the custard cups. Bake until the flan is firm and just set for about 30 to 35 minutes. When you tap the edge of the ramekin, the flan should still slightly wobble in the center. (Don't worry if it seems undercooked; it will continue to cook as it cools).

You can also insert the tip of a knife into the custard near the center; if the flan is still liquid, it needs more time in the oven. When the flan has started to set, remove the roasting pan from the oven, careful not to spill the hot water.

Let the flan cool while sitting in the water bath until the ramekins are cool enough to handle. Remove the ramekin from the water bath, transfer it to a rack, and let the Chocolate Flan cool completely; then cover tightly with plastic wrap and refrigerate overnight.