Cup of Yum
1. In a large bowl, dissolve the yeast in the milk and add 1 cup (150g) flour. Mix well, cover with plastic wrap, and set aside for 1 hour at room temperature, away from drafts.
2. Mix all the ingredients of the brioche except the butter.
3. Thoroughly knead the dough with the stand mixer or by hand, then add the butter little by little and knead until you obtain a dough that pulls away from the sides of the bowl.
4. Do not hesitate to add a little flour gradually if the dough is too sticky.
5. Cut the dough into the shape of guaguas de pan. To do this, make a template in a cardboard sheet placed on the dough, and cut it with a small sharp knife.
6. Renew the operation until the dough is used up.
7. Place the guaguas de pan, well spaced, on a baking sheet lined with parchment paper.
8. Let it rise again for 30 minutes.
9. Brush with the beaten egg yolks.
10. Bake in an oven preheated at 350F/180C for about 15 to 20 minutes or until golden brown but not too dark.
11. Allow to cool completely before proceeding with the decoration.

Decoration

Cup of Yum
1. Mix the icing sugar and water to obtain a homogeneous paste.
2. The water must be incorporated little by little until a paste with the consistency of glue is obtained.
3. Divide the preparation into as many parts as desired colors. Add select coloring to each preparation. If the food coloring is liquid, then rectify by adding a little icing sugar if necessary.
4. Use a syringe, a decoration pen or a small freezer bag with the tip cut to decorate the buns.
5. Place the guaguas in a cool place and let the icing dry completely before handling.