Prepare the Batter:
Combine sourdough discard, flour, sugar, and milk in a bowl. Mix until just combined.
If using the overnight method, cover and let sit at room temperature overnight.
For the same-day method, proceed to the next step.
Add Remaining Ingredients:
Whisk in eggs, melted butter, baking powder, and baking soda. Stir gently until incorporated. Do not overmix.
Heat the Skillet:
Preheat a non-stick or cast-iron skillet over medium-low heat. Add a small pat of butter to grease the surface.
Cook the Pancakes:
Pour 1/4 cup of batter onto the skillet for each pancake. Cook until bubbles form on the surface and the edges look set (about 2 minutes).
Flip and cook the other side until golden brown (about 1-2 minutes). Adjust heat as needed.
Serve:
Stack the pancakes and top with your favorite toppings like maple syrup, fresh berries, or whipped cream. Serve immediately.