My great-grandmother used to make a similar recipe that her mother taught her, who came to live in Chilean Patagonia from Switzerland, the recipe was also called Gateau and made with Rhubarb but you can also do it with green apples or berries. The dough in this recipe, is made with flour and lard or butter and a pinch of salt, like a pastry. The dough is pacled uncooked on the mold, inside is the rhubarb mix with sugar and covered with a more liquid mixture called "Papeta", made with 3 eggs, flour and milk or water (similar to the mixture of crepes), and butter cubes are placed on top and finally sprinkled with sugar, then everything is cooked in the oven.
Pour une plus jolie présentation c'est pas le papier qu'on coupe mais on égalise la pate!! lol et on fait la pate soi même aussi surtout quand on est youtubeuse, après chez soi on fait ce qu'on veux