Cheesecake Brownies

1 family size brownie mix prepared as directed.
1-8 oz pkg cream cheese, softened
1/3 c sugar
1 egg
1/2 t vanilla

Prepare brownie mix as directed.  Spread in greased 9x13. Beat cream cheese with mixer until smooth.  Add sugar, mix.  Add egg and vanilla, mix.  Pour over brownie mixture.  Cut through with knife for marble effect.  Bake at 350 for 35-40 minutes or until cream cheese is lightly browned.