Combine the yeast and the warm water in a large bowl. If using active dry yeast, let the mixture sit for a bit (5-10 mins) until it starts to bubble up then move on to step 2. If using instant yeast, you don't *need* warm water (although I find it helps the dough rise faster) and you can immediately mix together all of your dough ingredients without waiting for the yeast to bubble up.
Add the sugar, salt, whole wheat flour, and bread flour to the water and yeast mixture. Stir until you have a scraggly dough and have saturated most of the dry spots.
Cover the bowl and let this rise somewhere warm for 30 minutes.
After 30 minutes, complete your first stretch and fold. Instead of kneading this bread, you are just going to do what is called a “stretch and fold.” Basically, with slightly damp hands (just run them under water briefly) you will pull up the sides of the dough in the bowl and fold them inwards. Once you have completed this first stretch and fold, let the dough rise again for another 30 minutes.
After the second 30 minutes, complete the second stretch and fold. Let the dough rise again for 15 more minutes.
Now you are going to shape the rolls. Sprinkle some flour onto a countertop or work surface and tip out your dough onto the surface. First, divide it roughly into 12 equal pieces. Then, take each ball of dough and pull the sides into the middle gently, pinching them together. I like to pinch this seam together two to three times just to make sure I'm creating enough tension on the surface of the dough. Flip the whole roll over so the seam is facing down and place on a baking sheet lined with parchment paper. Feel free to pop any large air bubbles if you want to!
Repeat this with the other 11 pieces of dough. Cover with a towel or cling film and place in the fridge for 10-20 minutes or just while your oven preheats.
Preheat your oven to 450 F (230 C) and place a metal or cast iron pan/tray on the bottom rack of the oven to heat up and start boiling some water (1-2 cups) on the stove.
Once your oven is preheated, remove the tray of rolls from the fridge. Dust the tops with some extra flour, using your hands to spread it evenly on the surface of the dough.
Wet the blade of a very sharp knife or razor blade with a bit of water, and then score each roll with a cross on top.
While wearing oven mitts and being very careful, pour about 1-2 cups of the boiling water into the pan in the bottom of the oven. Quickly place the baking sheet with the rolls into the oven on the rack above the metal tray and immediately close it. Bake for about 15 minutes. They may need a few minutes longer depending on your oven but just check the bottoms of the rolls. Once they are browned and sound hollow when you tap them, they are done!
Remove from the oven and let cool for at least 10-15 minutes before slicing and eating!