In a large bowl, whisk together the flour, sugar, baking powder, and salt.
In another bowl, mix the beaten egg, milk, melted butter, lemon juice, and lemon zest.
Add the wet ingredients to the dry ingredients and stir until just combined. Fold in the poppy seeds.
Heat a lightly oiled griddle or frying pan over medium-high heat.
Pour or scoop the batter onto the griddle, using approximately 1/4 cup for each pancake.
Cook until pancakes are golden brown on both sides; serve hot.