Chewy Oatmeal-Raisin Cookies

Makes 24
1 1/2 cups old-fashioned rolled oats (not quick-cooking)
1/2 cup all-purpose flour (spooned and leveled)
1/2 cup raisins
1/2 teaspoon baking soda
1/2 teaspoon salt
6 tablespoons unsalted butter, room temperature
1/2 cup packed dark-brown sugar
1/4 cup granulated sugar
1 large egg
1 teaspoon pure vanilla extract
Directions
Preheat oven to 350 degrees. In a medium bowl, whisk together oats, flour, raisins, baking soda, and salt; set aside. Using an electric mixer, beat butter and sugars until light and fluffy, scraping down bowl as necessary. Add egg and vanilla; beat until combined. Gradually add oat mixture; beat just until combined.
Drop dough by rounded tablespoonfuls, 2 inches apart, onto two baking sheets. Bake until cookies are golden brown but still soft, 12 to 16 minutes, rotating sheets halfway through. Cool 5 minutes on sheets; transfer cookies to a wire rack to cool completely.