I got the recipe from an advertising flyer in Women's Day about 5 years ago. It is from the people at Eagle Brand.

Preheat oven to 350 degrees. Grease bottom only of a 9" springform pan. Prepare brownies according to package directions. Pour mixture into pan a bake for 35 minutes or until center is set. ( I always use the toothpick method.) After removing bottom layer from oven, reduce temperature to 300 degrees.

Halfway through baking time start cheesecake:

In a large mixing bowl with electric mixer, beat cream cheese until smooth. Add sweetened condensed milk and continue mixing to a smooth consistency. Add eggs and vanilla. Mix well. Stir in miniature chocolate chips by hand. Pour mixture over the brownie layer. The brownie need not be cooled before adding cheesecake mixture. Make sure that the temperature of the oven has cooled to 300 degrees before adding the cheesecake. Bake for one hour or until center is set. Cool slighty. Refrigerate for at least 4 hours before serving.

This recipe will only take about 15 minutes to prepare, it is that easy. Enjoy.