I could use some ideas on this.

This is a device I use to increase my counter space. It is coated in of 3 coats of Polyurethane. It is angled downward to drain off water.

I put things on it like bowls, glasses, etc.  
[![enter image description here][1]][1]

How can I keep the board from sliding forward?  
[![enter image description here][2]][2]


  [1]: https://i.sstatic.net/jCBm7.jpg
  [2]: https://i.sstatic.net/kSPoz.jpg