Years ago in culinary school, one of my favourite learned skills was how to use cream in savoury dishes. With the right flavour combination, cream can make almost any dish luxurious, decadent and satisfying. It usually does best with a splash of something acidic – like white wine or lemon juice – a blob of Dijon mustard and a grate of fresh nutmeg, but it can equally elevate dishes on its own (mashed potatoes).

Soups, sauces, desserts – where would we be without cream? When I moved to Ireland in 2013, I couldn't believe the amazing taste and quality of the dairy products we enjoy here.

This gratin celebrates these great Irish ingredients and is a delicious, hearty side dish made with Irish potatoes, celeriac (or celery root), cream, butter and little else. You can top it with whatever you like. I used breadcrumbs made from the ends of a sourdough loaf. The end result was fantastic, but you could always use shop bought bread crumbs or even crushed cream crackers mixed with melted butter.

With a nicely seared steak and some green veggies, this gratin will make your dinner plate sing. Remember, once your celeriac and potatoes are peeled they will begin to oxidise, which can make them turn black - to avoid this, store them in cold water until ready to assemble.

Celeriac and potato gratin

Serves eight

Ingredients:

1 medium celeriac, peeled and stored in cold water

2 large potatoes, peeled and stored in cold water

500ml cream

Two tbsp + 60g butter, melted

1 tsp Dijon mustard

Pinch of fresh nutmeg

1 large clove garlic, grated

2 tsp salt

1/2 tsp black pepper

Directions

1. Preheat your oven to 180°C. Generously grease a medium sized casserole dish with butter and set aside.

2. Prepare your root vegetables. Using a sharp knife, slice the ends off the celeriac so it stands firmly on the cutting board. Carefully slice along the sides of the celeriac; removing the tough outer peel. When the sides are peeled, trim around the base to remove any dirty bits.

3. Slice the celeriac into quarters and then slice the quarters as thinly as possible (I use a mandolin for this and recommend you do the same –slices of equal thickness cook more evenly).

4. Peel and slice your potatoes. Store the sliced vegetables in a bowl filled with cold water; this will keep them from oxidising and turning black.

5. Make the cream sauce: in a saucepan, add the cream, salt, pepper, Dijon and freshly grated nutmeg. Bring to a boil and remove from the heat. Place the cream in a jug so you can easily pour it over the vegetables.

6. Place piece of bread in a food processor and pulse to make fine breadcrumbs. Mix the breadcrumbs with the 60g of melted butter and set aside.

7. Assemble the gratin: lightly dry the sliced vegetables on a piece of paper towel and begin layering in the casserole dish - first celeriac, then potato. Keep layering until all the vegetables are used.

8. Carefully pour the hot cream over the sliced vegetables and top with the breadcrumb mixture.

9. Cover with foil and bake for one hour. Remove the foil and bake for an additional 15-20 minutes to ensure the breadcrumbs are well browned.

10 Serve hot with a protein of your choice, or chill overnight if you want to get the perfect slice (it's messy if you serve it hot from the dish).

*This will keep in the fridge for up to four days.