Place the potatoes in a large pan of salted water and bring to the boil. Cook for about 15–20 minutes, or until the potatoes are tender when pierced with a knife.
Drain the potatoes and squeeze them through a potato ricer back into the pan.
In a separate pan, bring the milk to the boil and add the finely sliced cabbage. Cook for a couple of minutes until the cabbage is tender.
Place the pan of potatoes over a medium heat and gradually beat in the butter until smooth, then add milk and cabbage into the potatoes and mix thoroughly. Season with salt and pepper (if you like spice – give it a really good hit of black pepper to spice it up).
In a large heavy based pan over a high heat add your oil and fry your Irish beef mince until golden brown then add your garlic, onion and carrot and cook for a further 5 minutes.
Add your flour and stir well for 1 minute before adding your stock and stout and allowing to cook for 2 hours over a low heat.
Once cooked and thickened add your peas, stir well and transfer into a suitable roasting pie tin before adding the colcannon mash topping and popping into a preheated oven until crispy on top.