Finely crush weetbix between fingers and place in the base of a small food container. Add in the drinking chocolate powder and reduced-fat milk (or alt), and mix until well combined. Allow to sit for a few minutes as the weetbix will start to absorb the liquid.
Meanwhile, in a separate bowl/ container, combine the yoghurt, raspberries, and protein powder and stir until well combined.
Press the base of the weetbix down firmly, using a spoon, and then add the yoghurt 'cream' on top of the weetbix base.
Finally prepare the 'chocolate sauce' topping - in a small bowl, combine the cocoa powder, SF maple syrup, and reduced-fat milk and stir until well combined. Pour over the top of the yoghurt layer, twirling at the base of the container to evenly distribute the top layer.
Refrigerate overnight or for a minimum of ~4 hours.