Recipe

Tropical bombe alaska

The mix of textures, flavours and temperatures combine in the classic king of desserts, the bombe alaska, to create a sensationally sweet dish.

  • 45 mins cooking
  • Serves 16
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Ingredients

Coconut sorbet
  • 1 tablespoon liquid glucose
  • 3/4 cup (165g) white sugar
  • 1 3/4 cup water
  • 150 gram coconut powder
Tropical bombe alaska
  • 450 gram packet rectangular unfilled double sponge cakes
  • 2 cup (500ml) mango sorbet
Rum syrup
  • 1/4 cup (55g) caster sugar
  • 1/4 cup (60ml) water
  • 1 1/2 tablespoon dark underproof rum
Meringue
  • 3/4 cup (165g) caster sugar
  • 2/3 water, extra
  • pinch cream of tartar
  • 4 egg whites

Method

Tropical bombe alaska
  • 1
    To make coconut sorbet: Stir glucose, white sugar and ¾ cup of the water in medium saucepan, over medium heat, without boiling, until sugar dissolves. Bring to the boil; boil, uncovered, without stirring, 3 minutes. Cool. Whisk coconut powder and the remaining water in large jug until smooth; stir in glucose mixture. Churn in ice-cream machine following manufacturer's instructions.
  • 2
    Using serrated knife split both cakes in half lengthways. Using a 10-cup (2.5-litre) Dolly Varden pan or pudding basin as a guide, cut circles from sponge to fit base and top of pan. Grease pan or basin; line with plastic wrap.
  • 3
    Line base of pan with sponge. Line side of pan with sponge, cutting sponge to fit. Spoon in mango sorbet; freeze until firm. Top sorbet with a layer of sponge cut to fit, then coconut sorbet; freeze until firm. Top sorbet with remaining sponge, cover pan with plastic wrap; freeze overnight.
  • 4
    Make rum syrup. Stir sugar and the water in small saucepan over high heat, without boiling, until sugar dissolves. Bring to the boil; remove from heat, cool. Stir in rum.
  • 5
    Have egg whites at room temperature.
  • 6
    Turn frozen bombe onto serving plate; discard lining. Return to freezer.
  • 7
    To make meringue: Stir caster sugar and the extra water in small saucepan, over high heat, without boiling, until sugar dissolves. Bring to the boil, reduce heat, simmer, uncovered, until syrup reaches 115°C/240°F on a candy thermometer. When syrup reaches 115°C, start beating egg whites with cream of tartar in medium bowl with electric mixer until soft peaks form. While beating egg whites, bring sugar syrup to 121°C/250°F. With motor operating, gradually pour hot syrup into egg whites in a thin steady stream; continue beating until mixture is thick, glossy and cooled to room temperature.
  • 8
    Working quickly, spread meringue all over sponge. Using a blowtorch, brown meringue until golden. Serve with rum syrup.

Notes

You need an ice-cream machine to make the coconut sorbet, or you can buy either coconut sorbet or coconut gelato for this recipe, if you prefer. When making the meringue, it takes up to 15 minutes for the sugar syrup to reach soft ball stage and then only a few minutes to reach hard ball stage ­ the syrup must not change colour. As the meringue sets quickly, keep beating it until ready to spread over the bombe. Blowtorches are available from kitchenware and hardware stores. You can serve the bombe Alaska without browning it. You can use bought ice-cream or sorbet such as passionfruit, pineapple or banana instead of the coconut sorbet. You will need to buy 3 cups (750ml). If you are not going to eat the entire dessert, cover the cut surfaces with plastic wrap and freeze before it melts.