Preheat the oven to 170C / 338F and line a baking sheet with parchment paper.
Cook the sweet potato, peel then mash them until puree.
Mix flour, semolina, baking powder and salt then set aside.
In a large mixing bowl, cream the butter and sugar.
In a small bowl, whisk the eggs and vanilla extract well.
Add the eggs mixture to the butter mixture, mix.
Then, add the mashed sweet potato, mix. After that stir in the flour mixture.
Spoon the batter in the baking sheet forming 12 big cookies.
Sprinkle the chopped pecan over the cookies then press gently on each cookie trying to flatten it a bit.
Bake for 10-15 minutes. Let the cookies cool before serving.
