1. Prepare your bananas: In a medium bowl, thoroughly mash the ripe bananas with a fork until mostly smooth but with a few small lumps remaining for texture. Set aside.

2. Combine dry ingredients: In a large mixing bowl, whisk together the all-purpose flour, granulated sugar, baking powder, baking soda, and salt. Make sure there are no lumps and the ingredients are well distributed.

3. Mix wet ingredients (except discard): In a separate medium bowl, whisk together the egg, milk, melted butter, and vanilla extract until well combined.

4. Incorporate discard and wet into dry: Add the sourdough discard to the wet ingredient mixture and stir until just combined. Pour the wet ingredients (including the discard) into the bowl with the dry ingredients. Stir gently with a spoon or spatula until just combined. A few lumps are perfectly fine and even desirable; overmixing can lead to tough pancakes.

5. Fold in mashed bananas: Gently fold the mashed bananas into the pancake batter until evenly distributed. Do not overmix. Let the batter rest for 5-10 minutes while your griddle heats up; this allows the leavening agents to activate.

6. Heat your griddle: Heat a lightly greased griddle or large non-stick skillet over medium heat. You can test if it’s hot enough by sprinkling a few drops of water on the surface; they should sizzle and evaporate quickly.

7. Cook the pancakes: Pour about 1/4 cup of batter per pancake onto the hot griddle. Cook for 2-3 minutes per side, or until golden brown and bubbles appear on the surface of the pancake, and the edges look set.

8. Serve immediately: Transfer cooked pancakes to a plate and serve warm with your favorite toppings. You can keep cooked pancakes warm in a low oven (around 200 F / 95 C) while you finish cooking the rest of the batch.