• 1½ cups unbleached (all-purpose) flour
• 1 teaspoon baking soda
• ¼ teaspoon fine sea salt
• 8 tablespoons (1 stick) unsalted butter, at room temperature
• ½ cup granulated sugar
• ½ cup packed light brown sugar
• ½ cup creamy peanut butter
• 1 large egg
• ½ teaspoon pure vanilla extract
• ¾ cup jam (your favorite flavor)

Position the racks in the middle and lower third of the oven and preheat the oven to 375°F. Line two cookie sheets with parchment.

In a large mixing bowl, whisk together the flour, baking soda, and salt. Set aside.

In the bowl of a stand mixer fitted with the paddle attachment (or in a large mixing bowl, using a handheld mixer), cream together the butter, both sugars, and peanut butter on medium speed for 3 to 5 minutes, until light and fluffy. Add the egg and vanilla and beat for 1 to 2 minutes, until fluffy.

Add the dry ingredients in thirds, beating until just combined. Finish mixing by hand.

Use a small ice cream scoop to form the cookies, about 1 rounded tablespoon each, and place on the prepared cookie sheets, leaving 2 inches between them to allow for spreading. Flatten the tops with the palm of your hand and then use the tines of a fork to create a crisscross pattern on the top.

Bake the cookies for 10 to 12 minutes, rotating the pans halfway through the baking time, until they are golden brown. Let cool completely on a wire rack.

To make the sammies: Put a dollop of jam (about 1 tablespoon) on the bottom of one of the cookies, place another cookie right side up on top, and press together gently. Repeat with the remaining cookies and jam.

The cookies can be stored in an airtight container at room temperature for up to 3 days.