Preheat 350ºF/180ºC. Line a 8in x 12in (20cm x 30cm) baking pan with non stick paper.
Crush the chocolate cookies or grind in the food processor until fine crumbs. Combine with sifted flour and cocoa and remaining ingredients for base and press into prepared pan. Bake for 20 minutes.
For the Filling:
In a large bowl mix together coconut, condensed milk, cherries and food color (if using) spread evenly over the hot base and return to oven for a further 15 minutes.
Chocolate Topping:
Place chocolate and butter in a microwave safe bowl. Microwave for 20 seconds on high, stir and repeat. Microwave the chocolate in 3 x 20-second intervals, stirring between each. Allow to stand for a few minutes. Stir again. If the chocolate has not totally melted. Try another 10 seconds in the microwave. Be careful not to overheat or you will burn the chocolate.
Spread over slightly warm bar - the warmth of the filling will help you spread the chocolate topping
Allow the chocolate topping to set but not harden completely or it will be hard to cut into neat squares. You can cool the slice in the refrigerator until just set or leave at room temperature overnight to set. Cut into 30 squares.
Notes
Self raising flour can be substituted with 1 cup of all purpose flour plus 2 teaspoons baking powder.
I use "chocolate ripple" cookies which can be found in Australian supermarkets. However use your favorite cocoa cookie. Alternatively any plain sweet cookie can be used. Your base will simply be a little less chocolatey.
Be sure to use unsweetened desiccated coconut not sweetened.
Glace cherries are also known as Candied cherries. These are found in the baking aisle of the supermarket. If you can't find them, ask a store employee to help.
1 tablespoon of oil can be used instead of butter in the chocolate topping.
Allow to set until firm but not hard before cutting into squares.