These we have traditionally called crunchies. I have chosen to rename them, as there appears to be a breakdown in communication affecting technology. A biscuit is something which gives one stamina; a cookie, where most useful, allows a client and a server to recognize each other (after initial authentication).
250g butter or baking margarine
1 cup sugar
2 cups oats
1 cup coconut
1 cup cake flour
0,3 - 0,5 tsp sodium bicarbonate (or 1 tsp baking powder)
Method: melt butter and add sugar. Mix oats, coconut, and flour, and add to butter mixture; leaving about half a cup as a remnant. Frugally add a few tablespoons of water to ease the mixture. Add bicarb (or baking powder) to the remnant, remove the mixture from heat, and mix in the remnant.
Press mixture evenly into baking tray. Bake at 200°C for 25 minutes.