2 cups old-fashioned rolled oats
2 cups flour
3/4 teaspoon baking soda
1/2 teaspoon baking powder
1/2 teaspoon salt
1/8 teaspoon cinnamon
1 cup (2 sticks) unsalted butter, softened
1 cup packed light brown sugar
2/3 cup sugar
2 eggs, at room temperature
1 teaspoon vanilla extract
2 cups semisweet chocolate chips
1 cup chopped walnuts
In a large bowl, stir together the oats, flour, baking soda, baking powder, salt, and cinnamon.
In a separate bowl, blend the butter and sugars with an electric mixer until smooth, about 2 minutes. Add the eggs and continue to beat until fluffy, about 1-1/2 minutes. Blend in the vanilla extract.
Using a wooden spoon, stir the dry mixture into the butter mixture one half at a time. Mix in the chocolate chips and walnuts. Refrigerate the dough for 1 to 2 hours.
Heat the oven to 350 degrees. Line a large, preferably light-colored baking sheet with aluminum foil, then grease the foil.
Using a scant 1/4 cup per cookie, shape the dough into balls and place them on the sheet about 2 inches apart.
Use your fingertips to flatten each ball to 1/3 inch thick. Bake the cookies on the center oven rack for 13 to 14 minutes, turning the sheet about halfway through. When they're done, the cookies should be very lightly browned and still look moist. Don't overbake them.
Cool the cookies on the baking sheet for 2 to 3 minutes, then transfer them to a wire rack. Makes about 2 dozen cookies.
Customizing Cowboy Cookies:
Add some variety to your cookie jar by replacing the walnuts and chips with different mix-in combinations:
Coconut Cowboy Cookies: 1 cup of flaked sweetened coconut, 2 cups of chocolate chips, and 1 cup of chopped walnuts.
Cranberry White Chocolate Cowboy Cookies: 1 cup each of white chocolate chips and dried, sweetened cranberries.
Peanut Butter Cowboy Cookies: 2 cups of peanut butter chips or 1 cup each of peanut butter chips and chocolate chips.