Almond Sherry Christmas Trifle

Ingredients:
3 ounces almond paste (1/3 cup)
3/4 cup granulated sugar, divided
1 cup all-purpose flour, divided
1/4 teaspoon plus a pinch of salt, divided
6 large egg yolks
3 tablespoons whole milk
1 teaspoon pure vanilla extract
1/4 teaspoon pure almond extract
4 large egg whites at room temperature 30 minutes
1 cup sour-cherry preserves
Sherry syrup
Vanilla custard
1/3 cup sliced almonds
1/4 cup confectioners sugar
1 cup chilled heavy cream
3 tablespoons medium-dry Sherry
1 tablespoon sugar
Equipment: 2 (15-by 10-inch) 4-sided sheet pans; a 2 1/2 to 3-quart glass trifle or soufflé dish

Instructions:
Preheat oven to 350°F with racks in upper and lower thirds. Butter sheet pans, then line bottoms with parchment paper and butter parchment. Dust with flour, knocking out excess.
Break up almond paste with your fingers into a food processor. Pulse until coarsely ground, then add 1/4 cup sugar, 1/4 cup flour, and 1/4 teaspoon salt and process until very finely ground.
Transfer mixture to a large bowl and whisk in yolks, milk, and extracts.
Beat egg whites with a pinch of salt in a bowl with an electric mixer at medium speed until they hold soft peaks. With mixer at low speed, add remaining 1/2 cup sugar in a slow stream. Beat at medium-high speed until whites hold stiff, glossy peaks. Fold one third of whites into batter to lighten, then fold in remaining whites gently but thoroughly. Fold in remaining 3/4 cup flour.
Divide batter between pans, spreading evenly, and rap pans against counter a couple of times to release any air bubbles. Bake cakes, switching position halfway through, until pale golden and springy to the touch, 16 to 18 minutes. Cool in pans until warm. Invert onto racks lined with parchment. Carefully peel off parchment from tops and cool completely.
While cake layers cool, pulse preserves in cleaned food processor until smooth.
Trim 1/2 inch from edges of 1 cake layer with a serrated knife to make a 14-by 9-inch rectangle, reserving trimmings; with short end nearest you, halve cake lengthwise. Brush top with some of syrup, then spread 1/4 cup preserves over each piece, leaving a 1-inch border all around. Beginning with a short end, roll up each piece tightly to form a log. Repeat with remaining cake layer. (You will have 4 logs total.)
Spoon 1 cup custard into bottom of trifle dish.
Cut 1 log into 5 rounds with serrated knife, then halve each round. Brush generously with syrup all over. Stand half-moons, curved sides up, around edge of trifle dish (at bottom), arranging them snugly and pressing against side to help them adhere. Tear reserved trimmings into pieces, then dip in syrup and arrange over custard in center of dish.
Cut and brush remaining logs in same manner, arranging slices, curved sides down, against side of trifle dish above first layer (there may be some left over).
Add remaining custard. Brush any remaining cake slices with syrup and arrange in center over custard.
Chill trifle, covered, at least 8 hours.
Have ready an unoiled sheet of parchment paper or lightly oiled foil.
Heat almonds in a dry small heavy skillet over medium heat, stirring frequently, until almonds are hot but not colored. Add confectioners sugar and cook, stirring and tossing, until almonds are lightly toasted and sugar glaze is caramelized, 2 to 3 minutes (not all sugar on almonds will melt completely). Immediately transfer to parchment, spreading in 1 layer. Cool completely.
Beat cream with Sherry and sugar until it just holds soft peaks. Spoon over top of trifle and sprinkle with praline almonds.