Step 1

Preheat the oven to 350°F

Step 2

Place a casserole dish over medium heat and add the olive oil

Step 3

When the oil is hot, add the onion, garlic and carrots then cover

Step 4

Reduce the heat and let sweat for 5 minutes

Step 5

Remove the lid and increase the heat to high

Step 6

Add the ground lamb and cook until browned then stir in the tomato paste, hot stock and frozen peas

Step 7

Season with salt and black pepper, and simmer over low heat for 15 minutes

Step 8

Meanwhile, make the colcannon topping: Place the potatoes, whole and unpeeled, in a saucepan with the largest ones at the bottom and fill the pan halfway with water

Step 9

Cover the pan and place over high heat

Step 10

When the water begins to boil, drain off about half of it, leaving just enough for the potatoes to steam

Step 11

When the potatoes are cooked, about 30-40 minutes depending on their size, drain and peel (hold them in a kitchen towel if they are too hot to handle)

Step 12

Place in a warm bowl

Step 13

In a saucepan, heat the butter over low to medium heat until melted then stir in the leeks

Step 14

Cover and cook for 2-3 minutes

Step 15

Remove the lid and stir in the milk and nutmeg

Step 16

Heat until the milk has warmed through

Step 17

Mash the potatoes, gradually adding the warm milk and leek mixture

Step 18

Season to taste with salt and black pepper

Step 19

Transfer the lamb mixture to a medium-size pie dish and spoon the colcannon topping over it

Step 20

Brush the top with melted butter to get a crispy golden finish

Step 21

Bake in the oven for 25 minutes and serve