Butter and flour 13x9x2-inch baking pan. Prepare cake according to package instructions, substituting 2/3 cup Marsala for water. Bake cake and cool completely. Cut cake crosswise into thirds. Cut cake lengthwise into 1-inch-wide slices. Set aside.
Mix thawed frozen raspberries and 3 tablespoons sugar in large bowl. Set aside.
Using handheld mixer, beat egg yolks and remaining 3/4 cup sugar in large metal bowl until well blended. Beat in 1 cup dry Marsala. Place bowl over saucepan of simmering water (do not let bottom of bowl touch water). Beat until mixture triples in volume and registers 160°F on thermometer, about 6 minutes. Remove bowl from over water. Cool yolk mixture to room temperature, whisking occasionally.
Using electric mixer with clean dry beaters, beat 3/4 cup cream in large bowl until stiff peaks form. Fold whipped cream into yolk mixture.
Arrange enough cake slices in 12-cup trifle dish to cover bottom. Spoon 1 cup of raspberry mixture over cake, allowing some to show at sides of bowl. Pour 1 1/2 cups filling over; smooth top. Arrange enough cakes slices over filling to cover completely. Spread 1 cup raspberry mixture over, allowing some to show at sides. Pour 1 1/2 cups filling over. Arrange enough cake slices over filling to cover completely. Spread remaining raspberry mixture over. Pour remaining filling over; smooth top. Cover and refrigerate trifle at least 4 hours or overnight.
Using electric mixture, beat 3/4 cup chilled whipping cream to stiff peaks in medium bowl. Spoon into pastry bag fitted with large star tip. Pipe whipped cream decoratively over trifle. Garnish trifle with raspberries.