This is a dessert that represents the best aspects of Thanksgiving: deliciousness and fun. I'm going to break it down into simple, easy-to-follow steps, most of which can be done the day before. This Baked Alaska combines all of the warm flavors of autumn from apples, to caramel, to brown butter.
Let the ice cream soften by leaving it at room temperature for 30 minutes. With a rubber spatula, spread the ice cream in an even layer across the bottom of a 9 in. x 13 in. glass baking dish. Cover the dish with plastic wrap, and place in the freezer for several hours to harden completely.Peel, quarter, core, and slice the apples into 1/2 in. slices. Add the slices to a large mixing bowl and toss with the juice of the 1/2 lemon. Heat a large saute pan over medium high heat. Add 3 tablespoons of the butter. Once the butter has melted and begins to bubble, add the apples, 1/2 cup sugar, and the vanilla extract.Cook the apples for about 10 minutes, until tender.
Remove the apples from the heat, and pour onto a plate. Let them cool to room temperature, then refrigerate until completely cold.Heat a large saute pan over medium high heat. Add the remaining 2 sticks of butter to the pan. Once the butter is melted, whisk in the nonfat milk powder. Continue to whisk until the milk solids begin to brown and smell nutty and toasty, about 3 to 4 minutes.Using a fine mesh strainer, strain the solids from the butter, and discard the butter. Let the brown butter crumble cool completely before using.
To make the swiss meringue, combine the sugar, egg whites, and cream of tartar in a large metal (preferably copper) mixing bowl. Place the mixing bowl over a medium saucepan with about an inch of simmering water in the bottom, and whisk to combine.Continue to whisk over the steaming water, until the sugar is dissolved and the mixture is warmed through.Pour the warm egg white mixture into the bowl of a standing mixer fitted with the balloon whisk attachment. Whisk on high until stiff peaks have formed and the mixing bowl is cool to the touch. Refrigerate the meringue, while you assemble your other ingredients.
Preheat the broiler.To assemble the dessert, remove the baking dish from the freezer, and the apples and meringue from the refrigerator. Spread the apples on top of the ice cream. Sprinkle the crumble on top of the apples. Finish the dessert by dolloping the meringue over the top. Run the entire dish under the broiler for about 20 to 30 seconds, to brown the meringue. Serve immediately.