I know it's a few years later but I just saw this episode this past week (May 2003). Good luck!

Chocolate-Mint Nightcaps
Recipe By: Marcel Desaulniers
Source: Baking with Julia
Yield: 2 dozen

The Ganache
12 ounces semisweet chocolate, coarsely chopped
1 1/2 cups heavy cream
1 tablespoon fresh mint -- chopped

The Cookies
1 1/2 cups cake flour
1/4 cup unsweetened cocoa powder
3/4 teaspoon baking powder
1/4 teaspoon salt
2 sticks (8 oz.) unsalted butter at room temperature
3/4 cup sugar
4 large eggs
1 teaspoon pure vanilla extract

The Ganache:
Put the chocolate in a bowl and keep close at hand. Bring the cream and the mint to a boil in a saucepan over medium-high heat. As soon as the cream reaches the boil, pour it through a medium-gauge strainer onto the chocolate; discard the mint. Whisk the ganache until it is smooth and then pour it out onto a clean jelly-roll pan. Spread the chocolate to the edges of the pan with a rubber spatula and refrigerate for 30 minutes. (Spreading the chocolate in a thin layer hastens its chilling.) The ganache can be made a few days ahead and stored, covered, in the refrigerator. If, when you're ready to use the ganache, it has chilled too much and is unworkable, just let it warm a bit at room temperature -- it will be shiny and easily spreadable, the texture you want, in a few minutes.

The Cookies:
Set one oven rack in the center position and the other at the top and preheat the oven to 300 degrees. Line four baking sheets with parchment paper. (If you do not have four baking sheets, cut four pieces of parchment, drop the batter on the parchment as instructed, and bake in batches, transferring the batter-filled parchment to the baking sheets as they become available -- just remember to cool the baking sheets before using them again.

Sift together the flour, cocoa, baking powder, and salt onto a sheet of waxed paper and reserve.

Beat the butter and sugar for 2 minutes at medium speed in a mixer fitted with the paddle attachment or with a hand-held mixer; scrape down the bowl, increase the speed to high, and beat 1 minute more, until the mixture is pale and creamy. With the mixer at medium speed, add the eggs one at a time, beating until each egg is fully incorporated and scraping down the paddle and sides of the bowl as needed, Add the vanilla extract and beat for 30 seconds, then add the dry ingredients, mixing just 30 seconds more. Remove the bowl from the mixer and use a rubber spatula to finish mixing in the dry ingredients.

Baking the cookies: Drop a heaping teaspoonful of batter for each cookie onto the parchment-lined baking sheets, making 12 cookies per sheet and leaving room between each cookie for spreading. Bake the cookies, two sheets at a time, for 7 to 8 minutes, or until the cookies have just set, rotating the baking sheets top to bottom and front to back after 3 minutes. Cool on the baking sheets. Repeat with the remaining sheets of cookies. When completely cool, lift the cookies off the parchment and store in an airtight container until ready to assemble. The unfillled cookies can be kept in an airtight container at room temperature for 2 days or frozen for a month.

Assembling the Nightcaps: To construct the nightcaps, spoon the ganache into a pastry bag fitted with a plain 1/4-inch tip. Pipe about 1 tablespoon of ganache onto the tops of 24 cookies. Center 24 more cookies (domed side up) on the ganache and press them into place to make neat sandwiches. To form the "nightcap." decorate the top of each sandwich by piping about a teaspoonful of ganache in a small circle that spirals upward on itself (coil on top of coil) and ends in a curving point created by pulling away from the circle and letting a bit of the chocolate taper toward the edge of the cookie. Serve the cookies immediately.

Storing: Both the ganache and the cookies can be made ahead. However, the nightcaps should be served soon after they are assembled.