In a small bowl, combine warm water and sugar, then sprinkle the yeast on top. Allow it to activate for about 5-10 minutes until it becomes frothy.

Meanwhile, in a separate bowl, mix all-purpose flour and salt. Once the yeast mixture is ready, pour it into the flour mixture, stirring until a shaggy dough forms.

Lightly flour your workspace, then turn the shaggy dough onto the surface. Gently fold in the shredded sharp cheddar cheese and chopped scallions until evenly dispersed throughout.

Once the dough is mixed, form it into a ball and place it in a greased bowl. Cover the bowl with a damp kitchen towel and let the dough rise for about 1 hour, or until it doubles in size.

After the dough has risen, gently punch it down to release air. Turn it out onto a lightly floured surface, and divide it into equal portions. Shape each piece into a round muffin.

Preheat a cast-iron skillet over medium heat. Carefully place the shaped muffins into the skillet, cooking them for 7-9 minutes on each side.

Once your muffins are golden and cooked through, transfer them to a wire rack. Allow them to cool for at least 15 minutes before slicing.