Place the butter, brown sugar and granulated sugar in a large mixing bowl and beat on medium-high speed until very pale and fluffy (3 to 5 minutes).
Add the egg, egg yolk, and vanilla, beating until completely incorporated.
Scrape the bottom and sides of the bowl with a silicone spatula, then add the flour, oats, cornstarch, cinnamon, baking soda, and salt, stirring on medium-low speed just until all the ingredients are combined (do not over-mix).
Stir in the raisins.
Use a 1 1/2-tablespoon cookie scoop to drop balls of cookie dough onto the prepared sheets, allowing about two inches in between (for spreading).
Bake (one sheet at a time) on the center rack of the oven for 7 to 9 minutes, or until set around the edges and just barely beginning to turn golden.
Cool completely on the baking sheet, then transfer to an air-tight container for storage.
Soft & Chewy Oatmeal Raisin Cookies
Amount Per Serving
Calories 102Calories from Fat 27
% Daily Value*
Saturated Fat 2g13%
Vitamin A 115IU2%
Vitamin C 0.4mg0%
* Percent Daily Values are based on a 2000 calorie diet.