Rhabarberkuchen mit Makronenhaube

Description
German rhubarb squares

Dough

 * 10.5 ounces (300 grams) flour
 * 4.4 ounces (125 grams) butter
 * 3.5 ounces (100 grams) sugar
 * 4 egg yolks (use the whites in the meringue)
 * 1 egg
 * 1 packet vanilla sugar

Topping

 * 3.5 pounds (1.5 kg) rhubarb (6 – 7 large stalks)
 * 10.5 ounces (300 grams) sugar
 * 3 tbsp breadcrumbs

Meringue

 * 3.5 ounces (100 grams) ground almonds
 * 4.5 ounces (125 grams) sugar
 * 4 egg whites

Directions

 * 1) Sieve the flour into a large, flat bottomed bowl.
 * 2) Add the sugar and mix well.
 * 3) Cut the butter in with a pastry cutter.
 * 4) Separate 4 eggs; set the whites aside.
 * 5) Add the four yolks plus one whole egg to the flour and butter mixture; add the vanilla.
 * 6) Knead briefly (it will be very dry and crumbly—that's okay).
 * 7) Place the dough in the refrigerator for 30 minutes to rest.
 * 8) Wash and peel the rhubarb, and cut it in ½ to ¾ inch pieces.
 * 9) Line a cookie sheet with parchment paper.
 * 10) Don't grease the pan (or if you don't have parchment paper you can try it with a greased pan instead).
 * 11) Roll the dough out to about ¼ inch thick.
 * 12) Make a ridge around the edge to help keep in the juices (you could try to make this as a pie. This amount would probably make two small pies. The crust is thicker, denser, and sweeter than a pie crust, though).
 * 13) Poke holes all over the crust with a fork and bake in a preheated 400°F oven for 15 – 20 minutes.
 * 14) Mix the 10.5 ounces of sugar in with the rhubarb and let them sit together briefly to create some juice.
 * 15) Spread the breadcrumbs over the pre-baked crust.
 * 16) Spread the rhubarb evenly over the crust, along with the sugar/juices.
 * 17) Bake for 20 minutes at 400°F until the rhubarb is soft.
 * 18) Beat the egg whites until they are stiff.
 * 19) Slowly add 4.5 ounces of sugar and continue to beat until it's thick and creamy.
 * 20) Fold the ground almonds into the egg whites.
 * 21) Distribute the egg white mixture over the baked and still hot rhubarb cake and bake at 450°F for 10 minutes until the meringue is lightly browned.