Preheat oven to 350 degrees; grease a 9" springform pan.
Cream together the butter, peanut butter, sugar and salt.
Add flour and mix until crumbly.
Press dough into pan making sure it comes up the sides (about two inches).
Bake in preheated oven for 8-10 minutes or until lightly browned. While the crust is baking, melt the chocolate chips, butter and salt over medium heat.
Remove from heat; add sugar and flour, stir until combined.
Add the beaten eggs, stir until you get a smooth consistency.
Pour into par baked crust and bake an additional 20-22 minutes.
Remove from oven; cool for ten minutes, remove from pan & continue to cool.
In a small saucepan (or microwave) melt the chocolate chips and peanut butter; stir until combined then drizzle on top.