Vacherins with Raspberry Sorbet and Mixed Berry-Cardamom Sauce - sugar

Method

• Position 1 rack in bottom third and 1 rack in top third of oven; preheat to 200F.
• Line 2 large baking sheets with parchment paper.
• Using 3 1/4- to 3 1/2-inch-diameter cookie cutter as template, heavily trace 4 circles on each parchment sheet.
• Turn parchment over so that marked side faces down (circles will show through).
• Whisk sugar and cornstarch in medium bowl to blend.
• Using heavy-duty or handheld electric mixer on medium-high speed, beat whites in large bowl until foamy, about 1 minute.
• Add cream of tartar; beat until soft peaks form, about 1 minute.
• Add sugar mixture, 1 tablespoon at a time, beating until whites are very stiff and glossy, at least 4 minutes with heavy-duty mixer and 6 to 8 minutes with handheld.
• Scoop enough meringue into pastry bag fitted with medium star tip to fill 1/3 full.
• Pipe small dot of meringue under parchment in each corner of baking sheets.
• Press parchment onto dots.
• Starting in center of 1 marked circle, pipe meringue in continuous spiral to fill circle completely.
• Pipe 1 meringue circle atop edge of base circle, forming standing rim.
• Repeat, piping 2 more circles atop first, forming meringue cup.
• Pipe 3 more cups on sheet, filling bag with meringue as needed.
• Pipe 4 cups on second sheet.
• Bake meringues 3 hours without opening oven door (sides of meringues may settle slightly).
• Turn off oven; let meringues stand in closed oven over-night to dry completely.
• (Can be made 1 week ahead.
• Store airtight in single layer.)
• Whisk jam, sugar and 1/3 cup water in heavy medium saucepan over medium-high heat until sugar dissolves and jam melts.
• Boil until sauce thickens and is reduced to generous 3/4 cup, whisking often, about 7 minutes.
• Add berries and cardamom; stir gently.
• Remove from heat; let stand 1 hour to thaw fruit.
• Cover; chill at least 2 hours and up to 1 day.
• Scoop sorbet into vacherins.
• (Can be made 2 days ahead.
• Wrap tightly; freeze.
• If you freeze the vacherins, the meringues will be tender and chewy rather than crisp.)
• Spoon sauce over.
• Garnish with berries and mint.
• Serve with remaining sauce.