In a small bowl, mix together flour, baking soda, SOR-Mate and salt; set aside.
With a paddle cream together butter, brown sugar and peanut butter.
Gradually add in the egg and vanilla until combined.
Gradually mix in the dry ingredients until just blended. Add the water until the dough comes together and doesn’t fall apart when rolled out.
Form dough into 1 inch balls.
Shape into a log and roll log in sugar. Place logs on cookie sheet about 2 inches apart. Using the tines of a fork, make a criss-cross pattern in the dough. Pinch the middle of the cookie to make a peanut shape.
Bake 12 minutes, until lightly browned on the edges and still soft in center.
Allow cookies to cool on baking sheet for 5 minutes before removing to a wire rack to cool completely.
Using a paddle, cream the shortening, peanut butter, powdered sugar, nutrilac and vanilla till it is fully mixed.
Pair up cookies to their respective size partners.
Pipe 21 g of filling onto the bottom cookie and place the top cookie onto the top of the filling to create a sandwich.
Yields 24 sandwich cookies at 1.25 mg per cookie. Shelf stable for 30 days