In a large bowl, mix lemon zest and sugar until well combined. Add flour, baking powder, baking soda, and salt. Mix to combine, then set aside.
In a separate medium bowl, whisk together egg, buttermilk, melted butter, vanilla extract and lemon juice.
Make a well in the dry ingredients and pour in the wet ingredients. Stir until combined and moistened. Be careful not to over mix.
Add the batter to a piping bag (or a plastic sandwich bag if you don't have a piping bag) Pipe them into the pan in the shape of hearts.
Heat a griddle or skillet over medium heat. Coat with cooking spray or oil. For each pancake, drop 1/4 cup of batter onto skillet. Cook 1-2 minutes, until surface of pancakes have some bubbles. Flip carefully and cook another 1-2 minutes. Transfer to a plate and cover loosely with aluminum foil to keep warm. Make sure to coat the skillet before every pancake or batch of pancakes to prevent sticking.
Serve with your favorite toppings.