- With the rack in the middle position, preheat the oven to 180 °C (350 °F).Line a baking sheet with parchment paper.
- In a bowl, combine the flour, baking powder and cocoa powder.
- In another bowl, with an electric mixer, cream the butter and sugar until smooth. Add the eggs, milk and vanilla. Beat until the mixture is smooth. Stir in the dry ingredients with a wooden spoon.
- Scoop 15 ml (1 tablespoon) of dough per cookie on the baking sheet. Flatten slightly with moistened fingers.
- Bake for about 13 minutes. Remove from the baking sheet and let cool. Bake the remaining cookies.
- In a saucepan, off the heat, combine the sweetened condensed milk, egg yolks, butter and brown sugar. Cook over medium heat, stirring until it thickens, about 5 minutes. Stir in the vanilla, coconut and pecans. Pour into a bowl and let cool. Refrigerate until the mixture is completely chilled.
- Spread half of the cookies with 15 ml (1 tablespoon) of filling. Cover with a second cookie.