My Mom was on the way down to the Farm when I called her for the recipe she's used over the years, so I searched the web for this one.  It wasn't exactly the same, but it came pretty close.  Mini Chocolate Chips are key, although I'd recommend using more chocolate chips in the batter than a 1/2 cup.  

Chocolate Chip Cheesecake
Ingredients:
Crust: 1/4 cup butter, melted 1 1/2 cups Oreo cookie crumbs (about 18 cookies) Filling: 3 packages (8 oz. each) cream cheese, softened 1 can sweetened condensed milk (Eagle Brand) 3 eggs 2 teaspoons vanilla 1 cup mini chocolate chips 1 teaspoon flour
Directions:
Crust: Combine butter and Oreo cookie crumbs. Press into the bottom of a 9" springform pan. Filling: In a large mixer bowl, beat cream cheese until fluffy. Add sweetened condensed milk and beat until smooth. Add eggs and vanilla and mix well. In a small bowl, combine 1/2 cup of chocolate chips with the 1 teaspoon flour. Toss to coat. Stir into the cheese mixture. Pour over crust. Sprinkle the remaining chocolate chips over top. Bake for 1 hour at 300 degrees F, or until cake springs back when lightly touched. Cool to room temperature and then chill until serving.