In a mixing bowl, combine flour, sugar, yeast, and salt.
Add butter, warm milk, and eggs. Mix until a dough forms.
Knead the dough for about 10 minutes until smooth and elastic.
Place the dough in a greased bowl, cover, and let rise for 1 hour or until doubled in size.
For the topping, mix butter, sugar, flour, and vanilla extract until smooth.
Divide the dough into 12 equal pieces and shape into balls. Place on a baking sheet.
Flatten a piece of topping dough and place it on top of each dough ball. Score the topping with a knife to create a shell pattern.
Cover and let rise for another 30 minutes.
Preheat the oven to 350°F (175°C). Bake for 20 minutes or until golden brown.