In a large mixing bowl, whisk together the flour, sugar, baking powder, baking soda, and salt.
In another bowl, combine the buttermilk, egg, melted butter, and vanilla extract.
Pour the wet ingredients into the dry ingredients and stir until just combined; do not overmix.
Gently fold in the sliced strawberries.
Heat a non-stick skillet or griddle over medium heat and lightly grease with butter or oil.
Pour about 1/4 cup of batter for each pancake onto the skillet.
Cook until bubbles form on the surface and the edges look set, about 2-3 minutes.
Flip and cook for another 1-2 minutes until golden brown.
Serve warm with maple syrup, additional strawberries, or whipped cream.