Step 1

In a bowl, with an electric mixer on medium speed, beat butter, oil, 1 cup granulated sugar, and the powdered sugar until very smooth. Beat in eggs until well blended, scraping down sides of bowl as needed.

Step 2

In another bowl, mix flour, baking soda, cream of tartar, and salt. Stir or beat into butter mixture until well blended.

Step 3

In a small bowl, mix remaining 1/2 cup granulated sugar and the cinnamon. Shape dough into 1-inch balls, then roll each in cinnamon-sugar mixture. Place balls 3 to 4 inches apart on buttered or cooking parchment-lined 12- by 15-inch baking sheets.

Step 4

Bake in a 375° oven until edges of cookies are lightly browned, 12 to 15 minutes; if baking more than one pan at a time, switch pan positions halfway through baking.

Step 5

Using a spatula, transfer cookies to racks to cool completely.

Step 6

Note: Nutritional analysis is per cookie.