To a clean jar add 15 grams of active sourdough starter (it is recommended the starter has been fed within the past 12 hours).

Next, add the sugar and water and stir until it becomes milky.

Lastly, add the flour and mix until a dough-like ball is formed. You can knead it on a clean surface to ensure all of the flour has been absorbed.

Cover the jar loosely and allow it to rest for 10-12 hours.

Note: Ensure your sweet stiff starter has doubled in size before mixing the dough.

This dough can be mixed by hand or a stand mixer.

Begin by warming the milk either in the microwave or over low heat on the stove (I microwave it for 30-45 seconds).

Add the milk to a medium mixing bowl and whisk in the sweet stiff starter and sugar with a fork. It’s perfectly fine if the starter doesn’t fully break down.

Whisk in the eggs until combined, then add the flour and salt. Mix until a shaggy dough forms.

Cover the bowl with plastic wrap or a damp towel and allow it to rest for 45 minutes.

The butter is intentionally being left out here as it will be easier to knead in after the dough has rested.

Ensure the butter is softened enough, spread it around the dough, and dimple it in.

Then, fold the dough into itself a few times in the bowl and transfer it to a clean work surface that is lightly floured.

Knead the dough for 8-10 minutes or until it comes together. The dough will become stickier as you knead it. The butter will also stick to your work surface while kneading. Use a dough scraper to clean it up and work it back into the dough.

Try not to use more than a few tablespoons of flour during the kneading process.

If the dough starts to tear or you simply feel frustrated while kneading it, let the dough rest for 5-10 minutes and then come back to it.

The dough has been properly kneaded once it comes together, is smooth, elastic, and not as sticky. It will be a bit tacky & this is normal.

Once complete, place the dough in a buttered bowl and cover it for 45 minutes.

Allow it to rest in a warm place. Turn your oven on and then off and place the dough inside.

Perform 1 stretch and fold 45 minutes to an hour into the bulk fermentation to ensure optimal gluten development.

After the stretch and fold, allow the dough to rest for the remainder of the bulk fermentation (8-12 hours) or until doubled in size.

Avoid placing the dough anywhere warmer than 78°F, if it gets too warm, the butter can melt out and affect the texture.

The dough can be shaped and refrigerated overnight OR the dough can be refrigerated for up to 24 hours and shaped when ready to use.

When you’re ready to shape the dough, generously butter and lightly oil the baking pan to prevent sticking. Alternatively, you can line the pan with parchment paper.

Using a food scale, divide the dough into 9 equal portions (weighing between 80-85 grams each).

Shape each dough piece into a ball, starting by pinching the seams together into the center.

Place the dough in your hand and scoop it under itself repetitively to tighten the seams. You can also round it out & tighten it up with the palm of your hand and a flat surface.

Place each roll into the baking pan, cover with plastic wrap, and place into the refrigerator overnight. The rolls can be baked the same day—just let them rise for 4–6 hours, or until they fill the pan, then bake.

The following morning remove the dough from the refrigerator and allow it to rise in a warm spot (this can take 4-7 hours depending on the temperature). Mine take about 6 hours around 72 degrees F.

Avoid placing the dough anywhere warmer than 78°F.

The rolls are ready when they’ve puffed up to fill the pan and feel soft and airy to the touch.

Once ready to bake, preheat the oven to 375 degrees F and make the egg wash by whisking together the egg and water.

Brush the rolls with the egg wash and bake for 20-25 minutes or until golden brown. Check the rolls at 20 minutes.

Your rolls are perfectly baked when the tops are golden brown and the centers reach an internal temperature of 190–195°F (88–90°C)

Right after the rolls come out of the oven, brush them with melted butter and sprinkle with flaky sea salt for the perfect finishing touch.

These rolls are best enjoyed on the day they are baked. Store any leftover rolls in an airtight container at room temperature for 2-3 days.