Optional: substitute any food extract you prefer with the vanillalemon, orange, mango, food coloring/gel, cinnamon powder, cocoa powder
Heat the milk to 110°F either on stovetop or in a cup in the microwave for 20-30 seconds. It should be just warm to the touch. Stir in the yeast and 1 tablespoon sugar. Let stand for 5 minutes until it gets foamy. If it doesn't, the yeast dead and you'll need start again with new yeast.
Add the vanilla to the eggs, mix and set aside. Melt the butter and weight the sugar and flour.
In a mixer bowl add the 4.5 cups of flour, remaining sugar and salt. Stir through with fingers. Make a well in the center and add the egg and vanilla mixture, melted butter and the foamy, active yeast.
Mix on medium-low speed for 8 minutes (or mix by hand), until the dough becomes smooth and elastic. The dough will be slightly tacky. You can sprinkle 2-3 tablespoons of flour on the inside edge of the bowl to keep the dough from sticking.
Using a rubber spatula scoop and lift the dough from the bowl, spritz the inside of bowl with cooking spray. Place the dough back in the bowl, cover with a light kitchen towel and let rise in a warm spot for 2 hours or doubled in size (See Note 1).
In a bowl mix together the softened butter, powdered sugar, flour and vanilla until a smooth paste forms. Use as is or divide and add color and or flavors (See Note 2).
Divide the topping into 12 balls and cover.
Line 2 baking sheets with parchment paper or use silicone mats.
On a clean, floured surface scoop out the risen dough and divide in half (easier to handle). Roll each half into a thick log and divide lengthwise. Cut each half into 3 equal pieces. Repeat with other half. You should have 12 pieces of dough.
Cup your hand over a ball of the dough and rotate in a circular motion to shape into a ball. Place 6 rolls on each prepared baking sheets.
Roll the Topping balls: using plastic wrap so disks are large enough to cover the dough balls. I used a tortilla press with plastic wrap. Carefully peel off of the wrap and place over the top of each dough ball. Press gently to adhere. Using a sharp knife, cut a seashell design or any pattern you fancy. Repeat with remaining.
Let rise, covered, for 30 minutes. Preheat your oven to 350°F.
Bake 20 minutes or until the bottoms are golden brown. Cool for at least 10 minutes before serving.
Store any leftover conchas in airtight container for up to 5 days.
I either set the entire bowl in my microwave and close the door, place it in the oven with the light on, and I've even been know to turn the dryer on for a minute, then place the bowl in there, too. You just want a draft-free, warm place.
I divided the paste into thirds. I used ½ teaspoon cinnamon + 5 drops red food coloring in one third, 1 tablespoon cocoa powder in another and left the other original vanilla flavored.