Preheat oven to 350 degrees
Grease the bottom of a 9 x 13 baking pan or cover with parchment paper and set aside
Combine the cream cheese, sugar, flour, vanilla extract, salt and egg in a medium sized bowl.
Once combined add in your food coloring to what ever shade of green you like best.
In a large bowl, make you brownie batter using the 'Fudgy' instructions on the back of the box.
Pour the brownie batter into your pan and then pour the cheese cake filling on top.
Smooth out the filing so that is almost reaches the edges of the brownie.
Use a knife and swirl through the pattern to create a marbled effect.
Bake using the guidelines on the box according to your pan size and remove from oven when an inserted toothpick comes out mostly clean
Chill overnight and then cut into squares.