Preheat the oven to 350°F. Bring 1 quart of water to a boil.

Place the sugar in a heavy saucepan with 1/4 cup water. Cover the pan and cook over high heat for 2 minutes. Uncover the pan, reduce the heat to medium, and continue cooking the sugar for 5 minutes, or until caramelized (a dark golden brown). Do not stir.

Pour the caramel into the ramekins, rotating each to coat the bottom and sides with molten sugar. Take care not to burn yourself. (It's a good idea to wear oven mitts to protect your hands and arms. Caramel gives a terrible burn.) Breathe a sigh of relief, the hard part is over. Let the caramel cool until hard.

In a mixing bowl, whisk together the condensed milk, skim milk, eggs, egg substitute, vanilla, lemon, cinnamon and salt. Ladle this mixture into the ramekins. Set the ramekins in a roasting pan and pour 1/2-inch boiling water around them. Place the flans in the oven. Bake until set, 30 to 40 minutes. (To test for doneness, tap the side of one of the ramekins. The mixture should jiggle, not ripple.) Transfer the flans to a rack to cool, then refrigerate for at least 4 hours, preferably overnight.

To unmold, run the tip of a paring knife around the inside edge of each flan. Place a plate over the ramekin, invert, and shake until the flan slips loose. Spoon any caramel left in the ramekin around the flan.