Preheat oven to 350 degrees.

Lightly grease 9x9 pan with cooking spray or butter.

In a large bowl, combine sugar and butter and mix until soft.

Add vanilla and eggs, and mix thoroughly.

Fold in flour and cocoa, mix well but do not overmix.

Mix in 2 tbsp lightly warmed hot fudge. 

Mix well.

Pour into pan.

Spread remaining 3 tbsp of hot fudge across top of brownies - I make 3 long lines, then drag a spoon back and forth over the top of the brownies to make a design in the fudge. 

Bake until sides of brownies are crunchy and have slightly pulled away from the pan. Toothpick inserted in middle might not come out clean because of the hot fudge swirled on top, but if you can avoid the fudge, toothpick in middle should come out clean.