In a large bowl, combine the sugar, corn starch, baking powder, and salt.

Add the eggs to it and whisk well until all the ingredients are well combined and the batter appears like a pancake batter.

Melt 1 ½ cups of chocolate over a double boiler. Heat about 3 inches of water in a sauce pan and when the water comes to a simmer, reduce the flame. Add the chocolate to a stainless steel bowl and place it over the simmering water. Make sure that the top bowl with the chocolate does not touch the water. This could cause the chocolate to scorch. Make sure that the water is barely simmering.

Keep stirring the chocolate with a spatula until it melts completely and is smooth.

Melt the butter in the microwave gently and then add it to the melted chocolate. Mix well.

Slowly add this chocolate mixture to the prepared sugar/egg mixture and whisk gently to combine.

Add the remaining ½ cup of chocolate and the chopped pecans and fold in.

Transfer this dough to a clean bowl and wrap it with a plastic wrap making sure that the plastic wrap touches the top of the dough. This prevents skin formation in the top layer.

Refrigerate this dough overnight.

Preheat the oven to 350 F and line two baking sheets with parchment.

Remove the dough from the refrigerator.

Take about a small handful of dough in your hands. Roll it quickly and place it on the prepared sheet about 2 inches away from each other. Gently press each ball to flatten it slightly.

Bake the cookies for about 8 – 10 minutes rotating once in between. The cookies when done should have cracks on the surface and the corners would just begin to set. Also, the center would have a wet spot about the size of a quarter. Remove them from the oven at this stage and let it cool on the rack for about 10 minutes.

Carefully remove the cookies with the parchment sheet and let them cool on a rack.

Repeat with the rest of the dough. Once cooled, store in an airtight container.