I've adapted this from a recipe in David Lebovitz's wonderful The Perfect Scoop because I prefer a Philadelphia style to an egg-custard base as it's on the wrong side of rich. Also, I'm guessing that malted milk balls in the States are heavier than Maltesers are here so the weights he gives would make for a malteser ball bound with icecream rather than icecream with malteser bits in it.
Plus you don't need to chill the mixture overnight (you need to with an egg base)
This will work in any icecream maker (I have a cheapo bowl in freezer type)
Make a vanilla icecream with one of those 600 ml cartons of cream topped up to 750 ml with some full fat milk. You can use even less cream if you like (I just like to use it all up) but the amount of liquid is 750 ml.
Pour some cream ( about a third) into a pan with 150 g caster sugar. Dissolve over medium heat. Add 90g of Horlicks. Pour this back into the rest of the cream, adding a teaspoon of vanilla essence.
This mixture needs to chill down.
When you are ready to churn, add to the mixer, and while it's doing it, take one of those large bags of Maltesers (135g, or the boxes are 120g -- it's not critical) and chop up into quarters. Don't eat too many, but 135g is ample so won't matter if you scarf some)
Add the malteser bits to the icecream as you decant into tupperware.
This is seriously f*cking good icecream and have had many an overblown compliment on it.