To make this recipe sugar free, substitute 18 packets of Truvia for the granulated and dark brown sugars and use a sugar-free jam for the filling.
Preheat the oven to 350°F. with a rack in the center position. Coat a baking sheet with pan spray (even it is nonstick) or line it with parchment paper or a silicone baking mat.
In a small bowl, whisk together the flour and salt; set aside.
In a medium bowl, using an electric mixer and the paddle attachment, if you have one, beat the peanut butter, cream cheese, butter, and granulated and brown sugars on medium for 2 to 3 minutes, until the mixture is well blended. Add the egg substitute and vanilla and mix for 2 minutes longer. Scrape down the sides of the bowl with a rubber spatula. Add the flour on low for 1 minute, just until it is incorporated.
Set aside 2/3 of a cup of dough for the cookie tops. Scoop the remaining dough into 16 equal portions and roll it between your hands into balls. Use your thumb or index finger to press a hole about 1/4 inch deep into the center of each ball, gently pinching the dough to create a well about the size of a quarter. Fill the holes with 1/2 to 3/4 teaspoon of jam.
Roll out the remaining dough on a flat surface between two large pieces of plastic film until it is 1/8-inch thick. Peel off the top film and use a 1 1/2-inch round cookie cutter to cut 16 circles, re-rolling the scraps as needed. Use the tines of a fork to press cross hatch marks onto the flat cookie tops, dipping the fork into flour as needed to prevent sticking. If the dough becomes too soft to work with, freeze it for 5 minutes and try again.
Lay one cookie top over each of the filled cookies and press the tops and bottoms together all around the edges to seal in the jam.
Space the cookies evenly on the prepared baking sheet. Bake the cookies for about 15 minutes, until the dough no longer appears wet or shiny but has not begun to brown. Halfway through the baking time, rotate the pan from front to back.
Transfer the baking sheet to a wire rack to cool for 15 minutes, then transfer the cookies directly to the rack until they are completely cool. Store any leftover cookies in an airtight container at room temperature for 2 to 3 days.
Source: Sweet & Skinny by Marisa Chruchill