Cinnamon Conchas by King Arthur Baking

NOTES

1. From this King Arthur Baking recipe. There is also a blog post that goes into some detail about this sort of baked good.

2. While using a starter for these rolls isn't traditional, King Arthur adds this step to make the dough easier to knead, handle, and shape. 

3. On the Great British Baking Show in 2022, one episode included conchas and the bakers were instructed to use a pie plate to press the topping into think disks in Step 13.

4. Store any leftovers, well wrapped, for three days at room temperature; freeze for up to a month.

5. The blog post gives tips and ideas for variations (emphasis mine): 

"...substitute either a whole wheat or white whole wheat flour for the all-purpose flour in the starter. Both work well and make the dough a bit easier to shape... In the dough itself, I also replace half the all-purpose flour with white whole wheat, which lends a good bite without creating too much chew. In addition, I like to make my life easier and work with the dough cold, so after it’s doubled in size at room temperature, I stick it in the fridge for 12 to 24 hours."

INGREDIENTS 

Starter 

3/4 cup (170g) water 
2 tsp instant yeast 

1 cup (120g) all-purpose flour (or use white whole wheat flour; see Notes)

Dough

1-1/4 tsp (8g) salt 
2-3/4 cups (330g) all-purpose flour (or substitute half of flour with white whole wheat flour)
1/2 cup (99g) granulated sugar 
3 Tbl (43g) butter, softened 
2 large eggs plus 1 egg yolk (reserve the egg white for the topping)

2 tsp vanilla

Topping

1/2 cup (99g) granulated sugar 
1/4 tsp salt 
1 tsp cinnamon 
5 Tbl (71g) unsalted butter, softened 
2/3 cup (80g) flour 

1 large egg white (reserved from above)

PREPARATION 

To make the starter: 

1. Weigh your flour for the starter; or measure it by gently spooning it into a cup, then sweeping off any excess. 

2. In a medium-large bowl, add the yeast and water, cover the bowl, and let the starter rest for 1 hour, until it's bubbly. 

To make the dough: 

3. Weigh or measure your flour for the dough, then add it along with the rest of the dough ingredients to the starter. 

4. Mix and knead the dough — using your hands, a stand mixer, or your bread machine set on the dough cycle — to form a sticky, elastic dough. Resist the urge to add more flour; it won't clean the sides of the bowl as dough for a traditional sandwich bread (or even brioche dough) will. 

5. Let the dough rise, covered, in the mixing bowl (or in another bowl, if desired) for 60 to 90 minutes, or until it's doubled in size. It may be a bit slow, so allow it plenty of time. 

6. If you haven't taken the butter out for the topping, do that now, cut it into tablespoon-size pieces, and let it get soft.

To make the topping: 

7. In a medium bowl, mix together the sugar, salt, cinnamon, and softened butter until smooth. 

8. Stir in about half the flour until mostly combined, then add the remaining half, mixing to make a thick paste. (Note: You'll use the egg white later.) 

9. Cover the bowl and set the topping aside.

NOTE: After the dough is done proofing, continue with the recipe. 

10. Put parchment onto a baking sheet and lightly flour your work surface, transfer the proofed dough onto it, and divide it into 10 pieces (about 89g each). 

11. Roll each into a ball. (Probably a good idea to cover the remaining dough with a towel or with plastic wrap while forming the balls.)

12. Place the balls of dough onto the prepared baking sheet, leaving some space between them.

13. Then divide the topping into 10 portions (about 24g each), flatten each portion into a very thin 3" to 4" disk by placing portions between two pieces of parchment or wax paper, and rolling with a rolling pin or flattening with your fingers. Set these disks aside.

14. Lightly beat the egg white. Brush the top of each shaped roll with some of the beaten eggwhite, then gently place one disk on top of each roll. No need to shape the disk to "fit" the roll.

15. Flatten the rolls slightly, cover, and let the rolls rise for 30 to 45 minutes until they're noticeably puffy. 

16. While the rolls are rising, preheat your oven to 350°F with a rack in the center. 

17. Just before baking, use a sharp knife or lame to cut designs into the disk of topping, being careful not to cut into the dough below.

18. Use a second baking sheet if you have one to nest the first pan with the prepared rolls into it. This double-thick protection will help prevent the rolls' bottoms from over-browning as they bake. 

19. Bake the rolls for 18 to 24 minutes, until they're golden brown. 

20. Remove the baked conchas from the oven and let them rest on the pan until they're cool enough to handle. Enjoy rolls warm or at room temperature.