1Preheat oven to 350F.
2Place the gingersnaps in the mixer bowl and grind to a coarse powder.
3Add the pecans, brown sugar, and the melted butter. Mix until smooth. Line a pan with the mixture pressing with the palm of your hand.
4Bake for 12 to 15 minutes.
5Let cool, unmold, and cut into large pieces. Arrange the pieces on the bottom of the jars.
6Preheat the oven to 200 degrees Celsius.
7Peel the rhubarb and cut into 5 centimeter long pieces.
8Arrange the pieces in a baking dish. Sprinkle with powdered sugar. Cover the pan with aluminum foil and bake for for 20 minutes.
9Add the 2 tablespoons of grenadine to sweeten and color the rhubarb a little bit (which will still be green at this stage) and bake for another 10 minutes.
10Remove the rhubarb from the oven and let it cool.
11Place the cooked rhubarb pieces in the jars on top of the crust.
12In a saucepan, heat 65 grams of sugar and water. Bring the syrup to a boil, stirring occasionally, bring the heat up to 450 F.
13In a bowl, whip the egg whites. Add 1 tablespoon of sugar and beat until the whites form peaks. Continue whipping and lower the mixer speed while adding the boiling syrup.
14Continue mixing for about 10 minutes to cool the mixture, gradually increasing the speed while mixing.
15When the mixture is cool, put it in a pastry bag with a fluted tip
16Carefully place a little meringue into each jar and sprinkle with powdered sugar.
17Quickly brown the top with a blowtorch.