Firstly, break up the shredded wheat biscuits and set aside. Then weigh the butter and set aside. Melt the milk chocolate either in the microwave or over a bain-marie, and set aside. Then chop the mini eggs and set aside. Finally, grease and line an 8x10in tin and set aside.
Place the sugar in a large saucepan over a medium high heat. Cook, stirring with a silicone spatula, until the sugar has melted and turned a golden colour. Then add the butter whilst stirring continuously. The mixture will bubble up a lot at this point.
Turn the heat down to low, and pour in the condensed milk. Again stirring continuously. Finally, stir in the salt and melted chocolate. Then take off the heat, and thoroughly stir in the shredded wheat until completely coated.
Pour into the prepared tin, and using your spatula spread out until even. Then scatter with the chopped mini eggs, pressing them into the mixture slightly and leave to cool to room temperature. Then place in the fridge for at least 30 minutes to set. Then slice into 16 pieces.