The Starter:

In a mixing bowl, add 1/2 cup of cool water, 1/4 tsp instant yeast, and 1 cup all-purpose flour. Mix them together to make a soft dough. Cover tightly with lid or with plastic wrap, and let it rest at room temperature for 12 to 16 hours - or overnight. The starter will expand and become bubbly. Store the leftover yeast packet in the fridge for use the next day (shut opening closed with rubber band or tape)

The Dough:

Heat 2/3 cup of whole milk in a saucepan for about 1-2 minutes on medium heat. Pour the warm milk into a large mixing bowl, add in 1 tbsp of sugar, and whisk it in till dissolved. Continue whisking to let milk cool to 105 to 110 degrees F.

When milk is about 105 - 110 F, add in 2 tsp instant yeast (remaining packet from the day before), gently swirl it in to combine, and let it sit for 10 minutes, until it's foamy - which ensures the yeast works (if yeast is not active, throw out and start again with new pack of yeast). While waiting for yeast to proof, melt 5 tbsp of butter, and let it come to room temperature.

Then in the mixing bowl with milk-yeast mixture, add in 1/4 cup of ube halaya, 2 large eggs, all of the starter, 7 tbsp of granulated sugar, 2 tsp salt, 1 tbsp of ube extract, and the 5 tbsp of room temperature melted butter. Whisk together till combined. Then add 3.5 cups of all-purpose flour. Mix in the flour by hand, just until you get a cohesive dough.

If kneading by hand, when the dough is somewhat together, turn it onto a smooth clean surface, knead by hand for 15 minutes. If using a stand mixer, using the dough hook attachment, knead for about 5 minutes on medium-low speed (level 2 on a KitchenAid). You can also use a bread machine set on the dough cycle. The dough will be slightly sticky at first, but after kneading it should form a smooth cohesive ball. Keep kneading until the dough is elastic and passes the window-pane test.

Grease a new medium-sized bowl, and place the dough in it. Cover with plastic wrap, and let the dough rest at room temperature for 1 hour. Fold the edges into the center, flip it over in the bowl, recover with plastic wrap, and let it rise for another 1 hour.

In the meantime, cut 24 squares of edem cheese / queso de bola (or can also use gouda cheese). I'm cutting approximately half inch cubes of edem cheese. And put 1/3 cup of breadcrumbs in a small shallow pan for rolling the buns.

Lightly grease a smooth surface with vegetable oil to prevent dough from sticking. Turn the dough onto it, divide the dough into half, and roll the dough into 2 long logs. Divide each log with your bench scraper, into 12 equal pieces, so we end up with 24 small pieces of dough. Take each ball and lightly press down with cupped hand while doing circular motion - to tighten up skin. It will become obvious which balls are smaller / bigger. Redistribute dough accordingly so that the 24 balls are all approximately the same size. And re-do the circular palm motion till all balls have taught skin.

Line a 13 x 18-inch baking sheet with parchment paper. When you have 24 equal-sized balls with tight skin, take one at a time, flatten the dough out with your fingers to make a disc about 2 to 3 inches in diameter, and put a square of cheese in the center. Fold the dough into the center to cover the cheese completely. Firm up the dough again by placing the seam-side down, and rolling them under your tightly cupped fingers, similar to before, but with less pressure - pressing down hard will cause the cube of cheese inside to pierce through the top. Make sure the seam is sealed, so cheese will not melt out while baking.

Then roll the dough ball in the breadcrumbs till all the surfaces are covered in breadcrumbs. Transfer the bun onto the prepared 13 x 18-inch baking sheet lined with parchment paper. Repeat this with all 24 buns. Place the 24 buns into a big baking sheet with 6 buns across and 4 buns down. Space the as evenly as possible, as the buns will expand further.

Loosely cover the buns with plastic wrap, and let them rise for another 2 hours, until they're puffy, and almost doubled in size.

Towards the end of the 2-hour proofing time, remove all racks from the oven except for a rack at the lowest level. Then on this bottom rack place an oven-safe skillet or shallow baking pan to the right side of the oven. Preheat your oven to 350 degrees F, and start to boil about 2 cups of water.

When the oven is at 350 F and the buns are ready to bake, carefully pour the 2 cups of boiling water into the hot skillet that was in the preheated oven. Be careful of the resulting hot steam or splashing. Then uncover the buns, place a rack in the middle height of the oven, and place the pandesal buns on this middle rack, towards the opposite side of the oven as the boiling water below (in this case the left side, since boiling water was on the right side), so that the steam from the skillet can easily rise and waft onto the pandesal buns. The steam from the skillet will help the buns rise and help create a nice crust.

Bake for 20-25 minutes, until the tops are golden brown. Serve warm and enjoy! Can store at room temperature for 24 hours. Freeze in an airtight container to store for longer.