Coat springform with cooking spray and then line with plastic wrap. Let plastic wrap hang over the sides of the pan.
Thaw 6 cups frozen raspberries. Remove ice cream from freezer and soften.
Cut ladyfingers in length to be flush with top edge of plastic-lined pan; stand them, with rounded edge at the top, along the sides of the pan. Place additional ladyfingers in the bottom of the pan, squeezing them in tightly to cover completely, cutting to fit in small areas if needed. Sprinkle Amaretto over ladyfingers; set aside.
Purée raspberries in a food processor with the sugar. Press through a fine sieve into a large bowl. Add softened ice cream to raspberry purée, and combine well. Pour ice cream mixture into prepared pan with ladyfingers. Freeze cake, covered with plastic wrap, until frozen hard, about 6 hours.
To serve, remove cake from freezer and let soften in refrigerator at least 30 minutes and up to 45 minutes.
Remove cake from pan, discarding plastic wrap.
Whip heavy cream with sugar and almond extract until stiff peaks form. Garnish cake by piping cream along edge of cake with a large piping tip. Top cream with fresh or frozen whole raspberries.
Serve cake with sauce. Pass extra sauce at the table. Makes 10.
To make the sauce: In a food processor, purée raspberries with sugar and Amaretto (or almond extract) and force through a fine sieve into a bowl. Sauce may be made ahead, covered and chilled.Servings: 1 1/2 cups