Preheat oven to 375 degrees and line a baking sheet with parchment paper
Cream together the butter and sugar until smooth and fluffy with either a stand up mixer or hand hand mixer .
1 cup unsalted butter , 1 1/2 cups granulated sugar
Add one egg at a time , mixing as you go .
3 large eggs
Then add the vanilla extracts and blend completely .
1 Tablespoon vanilla extracts
In a separate bowl whisk together the flour , baking powder, cornstarch , and salt .
3 cups all purpose flour , 2 teaspoons baking powder, 1 Tablespoon cornstarch , 1/2 teaspoon salt
Slowly add a little of the dry ingredients to the wet ingredients . Mix until just combined.
Drop a heaping spoonful of dough onto the lined baking sheets about 2 inches apart . The scoop I use is 2.7 Tablespoons , a large amount for a nice sized cookie .
Bake about 12-14 minutes , the edges should be slightly brown. See notes
Let the cookies cool about 10 minutes on the baking sheet then transfer them to a cooling rack . Store these in a sealed contained up to 5 days .