In a bowl, combine warm milk, yeast, and a pinch of sugar. Let it sit until foamy.
Mix flour, sugar, and salt in a large bowl. Add eggs and butter, then pour in the yeast mixture. Knead until smooth and elastic.
Cover the dough and let rise for 1 hour or until doubled in size.
Roll out dough, cut into circles, and spoon vanilla custard into the center of each. Sprinkle with chocolate chips and fold edges over.
Place brioches on a baking sheet, brush with egg wash, and let rise for 30 minutes.
Bake at 350°F (175°C) for 20–25 minutes until golden brown.
Cool slightly before serving. Enjoy warm with a cup of coffee or tea.