Step 1: In a large mixing bowl, whisk together the all-purpose flour, granulated sugar, baking powder, and salt until well combined.
Step 2: In another bowl, whisk together the egg, milk, sour cream, oil, and vanilla extract until smooth and well blended.
Step 3: Pour the wet ingredients into the dry ingredients. Gently mix with a spatula or whisk until just combined. Be careful not to over-mix; a few lumps are okay.
Step 4: Heat your non-stick skillet or griddle over medium heat. Lightly grease it with oil or cooking spray.
Step 5: Pour about 1/4 cup of batter onto the skillet for each pancake. Cook until bubbles form on the surface and the edges look set, about 2-3 minutes. Flip and cook for an additional 1-2 minutes, or until golden brown.
Step 6: Transfer the pancakes to a plate and cover with a clean kitchen towel to keep warm while you cook the remaining pancakes. Serve warm with your favorite toppings.