Using an electric mixer cream butter and sugars. Add in vanilla.
In a medium bowl mix flour, salt and cream of tartar. Gradually add to butter mixture until combined.
Stir in pecans.
Wrap dough in plastic wrap and chill for one hour.
Preheat oven to 350 degrees. Line baking sheets with parchment paper and set aside.
Roll tablespoon size balls of dough and place on baking sheet spacing about 1 inch apart. Slightly flatten with palm of your hand or with a bottom of a glass.
Bake for 10-12 minutes, don’t overbake.
Cool on baking sheet for about 5 minutes. Using a spatula, transfer to a wire rack to cool completely.
Store in an airtight container.
Notes
To freeze, allow cookies to cool completely. Wrap cookies tightly in plastic wrap. Place in a freezer safe bag or container. Thaw at room temperature before serving.