Stir 3 Tbsp. instant espresso powder and 1 Tbsp. sugar into 2 cups boiling water to dissolve. Add 3 Tbsp. coffee liqueur (such as Tia Maria) and stir to combine. Let cool. Beat 4 large egg yolks, ⅓ cup dry Marsala, and remaining ½ cup sugar in a metal bowl set over a saucepan of barely simmering water using a whisk or handheld electric mixer until pale yellow and tripled in volume, 5–8 minutes. Remove bowl from heat. Beat 1 lb. (2½ cups) mascarpone into egg yolk mixture until just combined. Beat 1 cup cold heavy cream in a large bowl until it holds stiff peaks. Fold mascarpone mixture into whipped cream gently but thoroughly. Dipping both sides of each of 36 savoiardi (crisp Italian ladyfingers; from two 7-oz. packages) in coffee mixture, line bottom of a 13x9x3” baking dish with 18 savoiardi in 3 rows, trimming edges to fit if necessary. Spread half of mascarpone filling on top. Dip remaining 18 ladyfingers in coffee mixture and arrange on top of filling in pan. Spread remaining mascarpone filling on top and dust with cocoa. Chill, covered, at least 6 hours. Let tiramisu stand at room temperature 30 minutes before serving, then dust with more cocoa. Do ahead: Tiramisu can be assembled up to 2 days ahead; keep refrigerated. Editor’s note: This tiramisu recipe was first printed in the January 2009 issue of ‘Gourmet.’ Head this way for more of our best coffee-flavored desserts →