Preheat oven to 180c.

Grease and line a loaf pan (22 x 12 x 6cm/8½" x 4½" x 2½") with baking/parchment paper (leaving a 13cm/5" parchment paper overhang on all sides) and set aside.

In a large bowl, whisk together cream, garlic powder, parmesan cheese, and salt.

Peel and thinly slice the potatoes (I use a mandolin for this) placing the slices into the cream mixture as you go, making sure they are all submerged.

Place two layers of potato slices into the bottom of the pan.

Starting with this second layer, drizzle a little melted butter in between each layer as you continue with the remaining potato.

Once you have used all the potato slices, fold sides of parchment paper over the top of the potato, then cover with foil and bake for 1½ hours or until the potato is tender and there is no resistance when it's pierced with the tip of a sharp knife.

Once potato is cooked, allow it to cool slightly for 15 minutes then place another loaf tin of the same size on top and fill this second pan with something heavy (see my notes) then place it in the refrigerator overnight to compress.

Preheat oven to 180c.

Line a rimmed baking sheet with parchment paper and set aside.

To turn out the terrine, run a sharp knife around the edge of the terrine to loosen it.

Then invert the terrine onto a cutting board, and give it a good whack on the base and it should come right out.

With a large knife, trim off the rough edges of the terrine (for presentation - see my notes on how I use these off-cuts) then slice the terrine into 6 equal pieces (like a loaf of bread with really thick slices).

Place the slices cut-side-down onto the baking sheet and bake for 30 minutes, then turn over and bake for a further 10 - 15 minutes or until golden brown and crisp on the edges.