In a bowl, mix discard, milk, butter, sugar, and flour until a shaggy dough forms.

Knead lightly, cover, and let rest/rise for 8–12 hours (overnight works great).

Mix in salt and baking soda. Roll dough 1/2 inch thick on a floured surface.

Cut into rounds using a biscuit cutter or glass.

Sprinkle a tray with cornmeal, place muffins on it, and let rest 30–45 minutes.

Cook on a dry skillet over low-medium heat for 7–10 minutes per side until golden and puffed.

Cool slightly, then fork-split and toast to perfection!