Mocha Cheesecake Squares

1-1/4 cup all-purpose flour
1 cup sifted powdered sugar
1/2 cup unsweetened cocoa powder
1/4 teaspoon baking soda
3/4 cup cold butter, cut into 1/2-inch cubes
1 tablespoon instant coffee crystals
1 (8-ounce) package cream cheese, softened
1 (14-ounce) can (1-1/4 cups) sweetened condensed milk
2 large eggs
1/2 cup semi-sweet chocolate chips

Pre-heat oven to 350 F. In a medium mixing bowl, stir together flour, powdered sugar, cocoa and baking soda. With a fork, cut in butter until crumbly. Press into the bottom of a 9x13" baking pan. Bake for 15 minutes. Meanwhile, dissolve coffee in 1 tablespoon hot water and set aside. In a large mixing bowl, beat cream cheese until light and fluffy. Gradually beat in condensed milk. Add coffee mixture and eggs; beat just until combined. Pour over crust. Bake for 20 minutes or until set. Allow to cool completely on a wire rack, then cover with plastic wrap and refrigerate. When firm, cut into 1.5-inch squares. Melt chocolate chips in the top of a double boiler over hot (not boiling) water. Transfer melted chocolate to a resealable plastic bag and with a scissors, snip off a tiny corner of the bag. Drizzle melted chocolate over squares.