Blend the condensed milk and the vanilla together in a bowl. Add the
powdered sugar a little at a time, blending each time until smooth.
Stir in the coconut. You should have a firm mixture. Pat the mixture
into a greased 9 x 13 inch pan and chill until firm.
Place the chocolate chips in a microwave-safe bowl and heat on high 1
minute at a time, stirring after each minute, until melted. Remove the
pan from the refrigerator and cut the coconut mixture into 1 x 2 inch
bars.
Set each bar on a fork and dip into the chocolate, completely coating
the bar. Let excess drip off, then set on waxed paper. Repeat for each
bar. Bars will take several hours to air-dry; if you are in a hurry
you can refrigerate the bars for about 30 minutes.