For ice cream
3 navel oranges
5 tablespoons sugar
1/2 cup English-style bitter orange marmalade
2 cups half-and-half
1 cup heavy cream
5 large egg yolks
1/2 teaspoon vanilla extract
1/8 teaspoon almond extract
1/4 teaspoon salt
Vegetable oil for pan
For florentines
1 cup slivered blanched almonds (4 1/2 oz)
1/2 cup sugar
31/2 tablespoons unsalted butter, softened
2 tablespoons light corn syrup
2 tablespoons heavy cream
1/4 teaspoon vanilla extract
1/8 teaspoon salt
2 teaspoons all-purpose flour
5 oz fine-quality bittersweet chocolate (not unsweetened), finely chopped
Special equipment: an instant-read thermometer; an ice cream maker; parchment paper;
a 2 1/2-inch fluted round cookie cutter; a pastry brush: an offset metal spatula
Make ice cream:
Finely grate zest from 2 oranges and cover zest with plastic wrap.
Squeeze enough juice from all 3 oranges to measure 1 1/2 cups.
Bring juice and 3 tablespoons sugar to a boil in a 1-quart saucepan and simmer until
reduced to about 3/4 cup, about 10 minutes.
Add marmalade and simmer, stirring, until melted, about 1 minute.
Remove from heat and cool.
Bring half-and-half, cream, remaining 2 tablespoons sugar, and grated zest to
a boil in a 2-quart heavy saucepan, stirring until sugar is dissolved.
Whisk yolks in a bowl until blended, then add 1/2 cup hot cream mixture in a slow stream, whisking.
Stir custard into cream mixture in saucepan and cook over moderately low heat,
stirring constantly with a wooden spoon, until thick enough to coat back of spoon
and registers 175 to 180�F on thermometer (do not let boil).
Pour custard through a fine-mesh sieve into a (clean) metal bowl and stir
in marmalade mixture, vanilla, almond extract, and salt.
Cool to room temperature, stirring occasionally, then chill, covered, until cold,
at least 2 hours.
Freeze custard in ice cream maker. While ice cream is freezing, oil bottom
and sides of a 13- by 9-inch baking pan, then line bottom lengthwise with a sheet of plastic wrap,
leaving a 2-inch overhang on each short end.
Spread ice cream in pan, smoothing top, then wrap pan in plastic wrap and
freeze until ice cream is hardened, about 4 hours.
Make florentines while ice cream hardens:
Put oven rack in middle position and preheat oven to 350�F.
Line 2 baking sheets with parchment.
Pulse almonds with sugar in a food processor until finely ground.
Cook almond mixture, butter, corn syrup, cream, vanilla, and salt in cleaned 1-quart saucepan
over moderate heat, stirring until butter is melted and sugar is dissolved, 2 minutes.
Remove from heat and stir in flour, then transfer batter to a bowl and chill until firm,
about 1 hour.
Roll level teaspoons of batter into balls and arrange about 3 inches apart on baking sheets.
Gently flatten balls to about 1 1/4 inches in diameter with a fingertip.
Bake cookies in batches until golden brown, 7 to 9 minutes.
Slide parchment with cookies from sheet onto a rack to cool completely.
Melt chocolate in a double boiler or a metal bowl set over a saucepan of
barely simmering water, stirring occasionally, then remove top of double
boiler or bowl from heat.
Working with 1 cookie at a time, lightly brush undersides of cookies with
chocolate and put, chocolate sides up, on rack.
Chill cookies in 1 layer until chocolate sets, about 5 minutes.
Assemble sandwiches:
Unwrap pan of ice cream and cut out 12 (2 1/2-inch) ice cream rounds with cookie cutter.
Lift out rounds with offset spatula and sandwich each between 2 chilled florentines,
chocolate sides in.
Cooks' notes:
� Florentine cookies (brushed with chocolate but not filled with ice cream)
can be made 2 days ahead and chilled, layered between sheets of wax paper,
in an airtight container.
� Ice cream sandwiches can be assembled 3 days ahead and frozen,
individually wrapped well in plastic wrap.
Let soften in refrigerator 5 to 10 minutes before serving.
Makes 12 sandwiches.