In a saucepan, bring the milk and heavy cream to a boil. Turn off the heat, add the ground espresso beans, and steep, covered, for 15 minutes.
In a bowl, whisk the eggs and yolks with 1 cup of the sugar until smooth. Set aside.
In a small, heavy-bottomed pan, dissolve the remaining 1/2 cup of sugar in the water. Cook the sugar over medium-high heat until caramelized. Do not stir the sugar as it cooks or it may recrystallize. Swirl the pan when the sugar begins to brown. Carefully pour the caramelized sugar into four 10-ounce ramekins or oven-proof custard cups.
Strain the espresso-infused milk mixture through a fine mesh strainer into the egg mixture. Whisk just to combine. Pour the espresso custard into the prepared ramekins, and gently spoon out any air bubbles off the surface of the custards. Transfer the custards to the baking pan. The towel will help keep the ramekins from shifting around when the pan is moved.
Pour boiling water into the baking pan until it comes halfway up the sides of the ramekins. Carefully transfer the pan to the center shelf of the preheated oven and bake for 40 to 45 minutes. When making custards it is important to remember that cooking times vary; fresher eggs cook faster than older eggs. To check the custards, gently jiggle a ramekin. If the custards are set, they shake as a firm unit; if underdone, waves of custard will shiver in the center. If the custards need more time, continue cooking, checking every 5 minutes, until done. Remove the set custards from the oven and the water bath.
Cool the ramekins for 15 to 20 minutes before refrigerating for at least 2 hours or overnight. Unmold each custard by inverting the ramekin onto a serving dish. The caramel serves as its sauce. Serve chilled.
From Gatherings and Celebrations by Burt Wolf, published by Doubleday. All rights reserved.