To the bowl of a stand mixer add sourdough discard, warm milk, granulated sugar and instant yeast. Let it sit for a minute so you can tell the instant yeast is activating (yeast smell, clumping together and a few bubbles). Then add the melted butter, salt, cornstarch and most of the flour. Reserve about 100 grams or ½ cup to add as you knead the dough. Mix until completely combined and add the rest of the flour a little bit at a time until the dough is tacky (not super sticky) and pulls away from the sides of the bowl. If the dough is overly sticky, add a little more flour. Knead the dough for about 5-7 minutes in the stand mixer or 7-10 minutes by hand.

Add a drop of oil to a bowl. Shape the dough into a ball and place into the bowl. Roll the ball around until it is completely covered in the oil. (The oil keeps the dough moist as it rises and makes it easier to handle once risen). Cover the bowl with plastic wrap or a kitchen towel and let rise until doubled in size. If your sourdough discard is cold, it may take longer for the dough to rise.

Cover the bottom of two 8 or 9 inch cake pans with parchment paper. Alternatively, prepare a half sheet pan with parchment paper. These rolls can also be separated into 12 pieces and fit in a 9 by 13 pan for a little larger roll.

Once the dough has doubled in size, dump it on the counter. Use a bench scraper or knife to separate the dough into 12 or 16 equal-sized pieces. Take each piece of dough and pull/pinch up the sides until it forms a ball. Roll the ball on the counter using your hand in a cupping shape (see video here) to seal the balls and create tension for the roll to rise.

Nestle rolls together in an 8 or 9 inch baking pan. Cover the pan and let the rolls rise again for about an hour until doubled in size.

Preheat your oven to 350ºF. Bake for about 22-25 minutes until lightly browned on top. Cover the tops with melted butter (I take a stick of cold butter and lightly touch it on the tops of all the rolls). Enjoy warm or freeze for later!