Preheat the oven to 350 degrees. Line an 8 x 8 pan with parchment paper or foil.

In a large bowl combine the butter, egg, brown sugar, and vanilla and mix until smooth. It's best to use a mixer but you can cream these ingredients by hand.

Add in the flour and mix until combined.

Fold in the cranberries and chocolate chips.

Pour the batter into the prepared pan.

Bake for 24-26 minutes.

Remove from oven and cool in pan for at least 1 hour.

Remove from pan and cut into 16 bars.