Mexican Conchas Sweet Bread

Dissolve yeast in warm water in the bowl of stand mixer. Add milk sugar, butter, salt egg, and 2 cups of flour. Stir together until well combined.
Switch to the dough hook attachment and add the rest of the flour. Knead on medium speed for 3 minutes until the dough pulls away from the side of the bowl. Add more flour, if needed.
Place the dough in a large, oiled bowl and turn the dough over to coat both side. Cover with greased plastic wrap and place in warm place to rise until doubled in size.

Beat the sugar, margarine and vanilla until light and fluffy. Add flour and mix until thick. Divide dough into three equal pieces and place each piece in a plastic sandwich bag. Add a few drops of food coloring gel and squish the dough until evenly colored. You may need to add more flour if the dough is too soft.
When the dough has risen, divide it into 16 even pieces. Form each piece of dough into a bun by tucking the corners under. (Do not roll between palms because this will make the dough tough.) Place the buns onto a baking sheet lined with parchment paper.
Take the sugar cookie topping and divide into 16 even pieces. Take each piece of dough and press it between your palms until it forms a cookie disc shape. Moisten one side slightly and place it on top of each bun, wet side down. This will help the topping adhere to the bun. Use a cookie cutter or a knife to lightly score rings or swirls into the top of the cookie topping to resemble conch shells. Let buns rise in a warm place for approximately 40 minutes.
Preheat oven to 375 degrees F. Bake buns for 18-20 minutes until lightly brown on the bottom.