Remove the ice cream from the freezer and leave to stand at room temperature to soften slightly. Put the chocolate chips in a heatproof bowl and rest it over a pan of gently simmering water, making sure the bottom of the bowl does not touch the water. Heat, stirring occasionally, for 2–3 minutes until the chocolate has melted. Remove the bowl from the heat.
Put the biscuits on a small baking sheet or a plate. Spread the melted chocolate over the top of each, sprinkle with the coconut and freeze for 5 minutes until the chocolate has set.
Turn 4 of the chocolate-coated biscuits over and put a scoop of the ice cream on each one, then sandwich with the remaining biscuits, chocolate-sides up. Serve immediately.