In a large mixing bowl, mix the sugar, oil, applesauce, and vanilla extract. Using a hand mixer, beat on low speed for 2 minutes until well combined.
1 cup (200 g) granulated sugar, ½ cup (120 ml) neutral oil, ½ cup (120 ml) unsweetened applesauce, 1 teaspoon vanilla extract
In another bowl, combine the all-purpose flour, cornstarch, baking soda, cream of tartar, ground cinnamon, and salt.
2 ¾ cups (330 g) all-purpose flour, 1 tablespoon cornstarch, 1 teaspoon baking soda, 1 teaspoon cream of tartar, ½ teaspoon ground cinnamon, ½ teaspoon salt
Add the dry ingredients to the wet ingredients and stir into a dough. The cookie dough should be thick, but soft. If it's too dry or firm, you can stir in 1-2 tablespoons of non-dairy milk.
Cover and chill the dough in the refrigerator for at least 30 minutes.
Preheat the oven to 375°F / 190°C and line baking sheets with parchment.
Combine cinnamon and sugar for the coating in a small bowl.
6 tablespoons (75 g) granulated sugar, 2 teaspoons ground cinnamon
Scoop the dough into slightly heaping tablespoon-sized portions, roll into balls using your hands, and then roll in the cinnamon sugar until fully coated.
Place the balls on the lined baking sheets, leaving about 2 inches or 5 cm between each ball to allow for them to spread.
Bake for 9-11 minutes or until the edges are starting to turn golden brown. Remove the baking sheet from the oven and tap it once on the counter to settle the cookies.
Cool the cookies for at least 10 minutes on the baking sheet before transferring them to a cooling rack to cool completely.