Activate yeast mixture:

Combine sugar and instant yeast in warm water; let sit.

Mix dry ingredients:

In a stand mixer bowl or large bowl, mix together flour, salt, diastatic malt, and softened butter.

Add yeast mixture:

Fit the dough hook, set mixer to low, and pour in the yeast mixture.

Knead dough:

Continue mixing on low until the dough forms a cohesive mass, about 5 to 10 minutes.

Hand-knead and shape:

Turn the dough out onto a counter and hand-knead by folding and stretching several times. Shape into a ball by pulling the top surface taut and tucking the edges underneath.

Oil the bowl:

Coat a large bowl with the reserved oil.

Oil dough ball:

Set the dough ball into the bowl, seam side down, then flip to oil all surfaces.

Refrigerate overnight:

Wrap the bowl with plastic wrap and refrigerate for 12 hours or overnight.

Preheat oven with steam pan:

Preheat oven to 400-450°F (200-230°C) when ready to bake. Set a heatproof dish on the oven's bottom rack.

Divide and shape rolls:

Split the dough into 8 equal pieces and form each into a round or oval shape.

Arrange on baking sheet:

Arrange the rolls on a baking sheet lined with parchment or a silicone mat.

Proof until doubled:

Drape a towel over the rolls and allow them to proof until nearly doubled in size, roughly 2 to 3 hours depending on room temperature.

Slash roll tops:

Lightly slash the top of each roll using a lame or sharp knife.

Add steam and bake:

Put the rolls into the hot oven. Right away, toss a handful of ice cubes or 1 cup (240 ml) of water into the dish to generate steam, then shut the door promptly.

Rotate and finish baking:

Bake for approximately 20 minutes until golden brown. For even color, rotate the baking sheet halfway through.

Cool on wire rack:

Take the rolls out of the oven and transfer them to a wire rack to cool.