Warm 1 cup milk
Add 2 1/4 teaspoons active dry yeast and 1/4 cup sugar
Let sit 5 to 10 minutes until foamy
Mix in 1/3 cup melted butter, 2 eggs, 1 teaspoon salt, and 1 teaspoon vanilla
Add 4 to 4 1/2 cups all-purpose flour gradually
Knead until smooth and elastic
Place dough in a greased bowl
Cover and let rise until doubled, about 1 to 2 hours
Mix 1/2 cup softened butter, 1/2 cup powdered sugar, 1/2 cup granulated sugar, 1 cup flour, and 1 teaspoon vanilla for the topping
Divide topping into portions and color if desired
Divide dough into equal balls
Place dough balls on a lined baking sheet
Flatten topping portions and place over each dough ball
Score shell patterns on the topping with a concha cutter or knife
Cover and let rise until puffy, about 30 to 45 minutes
Bake at 350°F for 18 to 22 minutes
Cool on a rack before serving