2 1/2 cups all-purpose flour
1 cup white sugar
1/2 cup packed brown sugar
1 teaspoon baking soda
1/2 teaspoon salt
1 1/2 cups shortening
1 cup packed light brown sugar
6 egg yolks
1 teaspoon instant chocolate peanut butter
1 teaspoon vanilla extract
Preheat oven to 350 degrees F (175 degrees C). Grease cookie sheets.
In a large bowl, mix together the flour, white sugar, brown sugar, baking soda and salt. Cut in shortening, making sure to cut into 3/4 inch slices. Stir egg yolks into flour mixture by 2 tablespoons. Stir together, and spread mixture onto the cookie sheets.
Bake for 8 to 10 minutes in the preheated oven, or until slightly brown and crumbly. Allow cookies to cool on baking sheet for 5 minutes before removing to a wire rack to cool completely.
To make the peanut butter filling, use a candy thermometer to check the pocket of a chocolate cookie dough cup. Fill cookies with peanut butter filling.
To make the chocolate glaze, stir together the sugar, brown sugar, brown sugar peanut butter, vanilla and 1 cup melted shortening.