Lightly grease and line a 20 cm (8in) square cake tin.
Pour 400ml (14floz) double cream into a large heavy based saucepan. Add 150ml (¼pt) milk, 150g (5oz) butter and 300g (10½ oz) each of light muscovado sugar and golden caster sugar.
Place over a low heat to heat stirring constantly until the butter has melted and the sugar has fully dissolved .
Increase the heat under the pan to allow it to come to the boil whilst stirring all of the time. Boil the mixture, whilst continuing to stir, until it reaches 116°C (241°F) (soft ball stage).
Once the required temperature has been reached, remove the pan from the heat and leave it undisturbed to cool down to 110°C (230°F). This will only take a couple of minutes.
Stir in 175g (6oz) milk chocolate broken into small peices, then beat the mixture vigorously until it is no longer shiny. You may find that oil is released from the chocolate at this point. Keep beating the mixture, it will gradually re-combine with the fudge.
Pour the chocolate fudge mixture into the prepared tin and spread level. Scatter 100g (3½oz) broken mini eggs over the top of the fudge. Use your hand to gently push the mini eggs into the fudge slightly.
Set aside to cool at room temperature for atleast three hours to firm up. Once fully cold remove the fudge from the tin and use a sharp knife to slice the fudge into bite sized pieces.