Preheat oven to 350°F.
In a small bowl mix flour and baking soda. Set aside.
In an electric mixer beat butter and sugars until smooth and fluffy.
Add salt, vanilla and eggs. Mix until combined.
With mixer on lowest setting add the flour.
Add chocolate chips and mix until combined.
Press the cookie dough into the pan of your choice (2-8 inch round baking pan or a large 12-14 inch flan pan with removable bottom). It will puff up during cooking so only fill the pan about half way. Make cookies with any left over cookie dough.
Bake in oven for 13-15 minutes. Remove and add marshmallows and other toppings.
Place back in the oven and continue baking for 8-10 minutes until brown around the edges and marshmallows have melted.
Transfer to a cooking rack and allow to cool completely.
Drizzle with melted chocolate if using. Let chocolate set before cutting.
Cut into wedges or squares. Serve whole on a large platter, pizza board or in a pizza box.