NOT NUTTER BUTTERS

Makes 2 to 3 dozen cookies.

Note: These cookies mimic Do-Si-Dos, the popular peanut butter sandwiches sold by Girl Scouts. From " Nancy Silverton's Sandwich Book" (Knopf, $25.95).

For cookies:

1 1/2 c. (3 sticks) unsalted butter, divided

1 vanilla bean

2 c. quick-cooking rolled oats

2 tsp. baking soda

2 tsp. kosher salt

3/4 c. granulated sugar

3/4 c. light-brown sugar

3/4 c. natural, chunky-style unsalted peanut butter, excess oil poured off and discarded

2 1/4 c. flour

For filling:

3 tbsp. unsalted butter

1/2 tsp. kosher salt

3 tbsp. powdered sugar

1/2 c. plus 1 tbsp. natural, chunky-style unsalted peanut butter

To prepare cookies: In a medium skillet, melt 1 stick of butter over medium heat. Using a small paring knife, split vanilla bean lengthwise. With back of knife, scrape out pulp and seeds, and add scrapings and pod to butter. Add oats and cook for 5 to 7 minutes, stirring constantly, until oats are lightly toasted and a golden-brown color. Remove and discard vanilla pod, transfer mixture to a large bowl and refrigerate.

In bowl of an electric mixer fitted with a paddle attachment, cream remaining 2 sticks butter, baking soda and salt on low speed for 2 to 3 minutes, until butter is softened. Add granulated sugar and light-brown sugar and mix on medium speed until mixture is light and fluffy, scraping down sides of bowl as needed. Add peanut butter and mix to combine. Turn mixer off and add oat mixture and flour. Turn mixer to low speed and mix another minute, until ingredients are incorporated and dough pulls away from sides of bowl and comes together in a ball.

Adjust oven racks to lower and middle positions, preheat oven to 350 degrees and line baking sheets with parchment paper. Using your hands, roll dough into 2-inch balls. Place balls on prepared baking sheet, 2 1/2 inches apart. Using heel of your hand, flatten balls into 2 1/2- to 3-inch discs. Using a fork, mark diagonal crisscross patterns over surface of each cookie. Chill until firm, about 15 minutes.

Bake cookies for about 16 to 18 minutes, until lightly browned and slightly firm to touch, rotating baking sheets halfway through. Remove cookies from oven, let cool for 2 minutes then remove cookies to a wire rack to cool completely.

To prepare filling: In bowl of an electric mixer fitted with paddle attachment, cream butter and salt on medium speed for about 1 minute, until butter is softened. Add powdered sugar and peanut butter and mix for another minute to combine. Flip a cookie over to make a bottom. Spread 2 teaspoons of filling in center of each. Place top cookie over filling, pressing gently to sandwich them together. Repeat with remaining cookies and filling. Serve with a tall glass of milk.