Preheat the oven to 170C/340F. Line a 16 cm round mold with baking paper.
Beat the eggs with the sugar and vanilla until pale and foamy.
Add the yogurt and whisk until combined.
Separately sift the flour and whisk it with the cinnamon and baking powder.
Mix the wet and dry ingredients until you have a smooth paste.
Peel and core an apple, cut it into cubes and add it to the dough.
Pour the batter and spread it evenly in the pan.
Place another apple, cored and thinly sliced, on top.
Pour the melted butter on top and bake the tart for 1h30.
