Put the coffee beans and cardomom pods in the work bowl of a food processor and pulse on and off several times to roughly chop - not grind - them. Turn the chopped beans and pods into a medium saucepan and add 1/2 cup of the sugar. Put the pan over medium heat and cook, stirring constantly with a wooden spoon, until the sugar starts to melt. Patience - this will take a few minutes. Once the sugar has melted, continue to cook, still stirring without stop, until the sugar caramelizes - you want the color of the caramel to be deep, almost mahogany. Now, standing away from the stove so you don't get splattered, slowly pour in the milk and 1 cup of the cream and all of the milk. Don't panic - the caramel will immediately seize and harden - it will all smooth out as the liquids warm and the sugar melts again. Bring the mixture to a boil and, when the sugar has melted and everything is smooth again, pull the pan from the heat. Cover the pan (we do this with plastic wrap at the Cafi to get a good seal) and allow the mixture to infuse for 20 minutes. 

Center a rack in the oven and preheat the oven to 300F. 

Working in a bowl that's large enough to hold all the ingredients, whisk the yolks and remaining 1/4 cup sugar together until the mixture is pale and thick. Strain the coffee-cardamom liquid into a measuring cup (discard the beans and pods) and add enough heavy cream to bring the liquid up to 2 cups. Very gradually and very gently - you don't want to create air bubbles - whisk the liquid into the egg mixture; skim off the top foam, if there is any. 

Arrange six 4-ounce espresso or custard cups in a small roasting pan, leaving an even amount of space between them, and fill each cup nearly to the top with the custard mixture. Carefully slide the pan into the oven; then, using a pitcher, fill the roasting pan with enough hot water to come halfway up the sides of the espresso cups. Cover the pan with plastic wrap (don't worry - it can stand the heat) and poke two holes in two diagonally opposite corners. Bake the custards for 40 minutes, or until the edges darken ever so slightly and the custards are set but still jiggle a little in the center when you shake them gently. 

Remove the pan from the oven and let the custards sit in the water bath for 10 minutes. Lift the cups out of the water and cool the custards in the refrigerator. (The pots de crhme can be prepared a day ahead and stored in the refrigerator; when they are cool, cover them with plastic wrap.)

To serve: The pots de crhme are at their best at room temperature, so remove them from the refrigerator and keep them on the counter for about 20 minutes before serving.