Sift together flour, sugar, baking soda, baking powder and salt.
In a separate bowl, beat the eggs and then beat in the buttermilk.
Add the egg and buttermilk mixture to the dry ingredients and whisk lightly.
Whisk in the melted butter.
Heat an electric skillet to low or a cast iron skillet over low heat. Brush with vegetable oil.
If using heart-shaped molds, brush them with vegetable oil. Set the pancake mold on the skillet and pour in less than 1/4 cup of batter (depending on the size of your molds), spreading it out to fill the mold.
Or you can pour slightly less than 1/4 cup of batter onto the greased electric skillet or cast iron skillet for each pancake.
Allow the pancakes to cook for about 90 seconds. Carefully remove the pancake molds if using, and flip the pancakes over to finish cooking.
Brush the skillet and the pancake molds before cooking more pancakes.
Notes
Substitute for buttermilk: Mix together 2 cups of milk with 2 tablespoons of white vinegar or lemon juice. Allow the mixture to sit for 5 minutes.