Adjust a rack to the middle position and preheat the oven to 350° degrees.
For the caramel: 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.
For the Coffee Flan: In a medium bowl, combine the evaporated milk with the espresso (this will help cool the espresso). Place all the remaining flan ingredients and the espresso mixture in a blender and beat on high speed until well blended.
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. Place the ramekin in a large roasting pan; fill a roasting pan with hot water to about 1 to 2-inch depth.
Bake the Coffee Flan until firm and set but still slightly jiggly in the center, about 35 minutes (Don’t worry if it seems undercooked; it will continue to cook as it cools).
Transfer the roasting pan to a rack and let the flan cool slightly in the water. Next, remove the pan from the water bath, transfer it to a rack, let the Coffee flan cool completely, and then cover tightly with plastic wrap and refrigerate overnight.
To unmold the Coffee Flan: Remove the flan from the refrigerator and let it sit at room temperature for about 10 minutes. 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 rim of the Ramekin, being sure to reach the caramel on the bottom; tilt the Ramekin slightly to allow a bit of the caramel into the gap. Carefully invert a rimmed round platter over the Ramekin. Grabbing both, carefully invert the flan onto individual platters. Pour and scrape the caramel onto the flan and serve! Enjoy!