Preheat oven to 350 degrees.
Mix baking soda and water. Set aside.
Cream together shortening, granulated sugar and brown sugar.
Add vanilla, egg and baking soda/water mix.
Gradually beat in flour, graham cracker crumbs and salt.
Mix in 1/2 cup of mini Hershey's Kisses by hand.
Spread in a greased 8 inch square pan.
Bake at 350°F for 18-20 minutes.
Remove from oven and turn the broiler on.
Sprinkle mini marshmallows over the bars.
Place under broiler, for 30-60 seconds, to toast marshmallows. Watch carefully because they toast quickly!
Turn oven off and remove the bars.
Sprinkle with 1/2 cup of mini Hershey's Kisses and return to the still warm oven for a couple of minutes to soften Kisses.