Put the eggs, flour, sugar, margarine, cocoa, milk and food colouring in a bowl and whisk for about a minute until pale and smooth.
Line a 24-hole mini cupcake tray with mini cupcake cases. If you don't have a suitable cupcake tray, double up the cupcake cases to create 24 thicker cases (this helps them keep their shape) and arrange on a baking tray.
Share the batter equally between the cases, then tap the tray on the countertop to level the batter.
Place your cakes in the oven for 10-12 mins until springy on top. Transfer to a wire rack to cool completely.
Make the cream cheese frosting
Beat the cream cheese and vanilla in a clean bowl to loosen.
Sieve in the icing sugar and whisk until smooth.
Pipe or spoon a little icing over each cake, except one.
With the last remaining cake, crumble it up as finely as you can and sprinkle it over the frosting on the other 23 cakes from a height to create decorative red speckles.
All the icing to set before placing in storage - it should firm up but won't dry out. Store in an airtight container - they’ll keep for a couple of days in a cool place.