This creamy, cheesy potato and leek gratin is the ultimate comfort food. This gorgeous potato side dish contains thinly sliced potatoes baked in a rich cheesy cream sauce with buttery leeks, finished with the most delicious golden crust. Ready in just under an hour!
I’ve made no secret that I love potatoes on here, and this recipe is no different: the combination of cheese, potatoes, and leeks are the peak of winter comfort food, in my eyes. Other potato recipes you have all loved recently include these super crispy roast potatoes, my Greek potatoes with whipped feta, and these epic cajun fries (like a homemade Five Guys fry!)
How To Make This Potato and Leek Gratin
I’ve included the exact recipe with the ingredient quantities and instructions in the recipe card below, but here is a quick overview.
Step 1) Prepping your ingredients
Slicing your leeks and potatoes is one of the most time-consuming parts of this dish, so I like to do this first. Cut the ends off your leek, then halve it down the middle lengthways before slicing thinly.
For your potatoes, wash them and peel them, then slice thinly. You could either use a mandolin to help you slice your potatoes nice and thin, or you could just use a knife and chopping board with extra case! (I slice my potatoes with my knife as I don’t own a mandolin. Just take care the potato doesn’t slip and put your fingers at risk!!)
Step 1) Saute your leeks
Start by sauteing your leeks in butter until they’re soft and fragrant, then add minced garlic to your pan.
Step 2) Make the creamy sauce
To make the cream sauce, we add white wine to the leeks, then pour in double cream, seasonings, and three-quarters of the extra-mature cheddar cheese. Reserve the remaining cheese to sprinkle over the top of the dish!
Step 3) Arrange the potatoes
Pour a spoonful of the leek mixture into the bottom of your baking dish, and then arrange your potatoes. I like to arrange them stacked upright to get more of the edges really lovely and crispy in the oven. I also think this looks a little more extravagant, but it’s not essential.
Step 4) Pour over the sauce
Pour your creamy leek sauce all over the potatoes, using your spatula to gently help ease the cream and leeks in the gaps between the potatoes if you can.
Step 5) Bake!
Scatter over the remaining cheese, and then bake the dish covered with foil for 30 minutes, followed by 20 minutes without. The top should be beautifully golden and crispy and bubbly when you remove it from the oven!
- 1 large leek
- 4 large potatoes, peeled and thinly sliced
- 2 cloves of garlic, minced
- 60ml white wine
- 250ml double cream
- 75g grated extra mature cheddar cheese
- 1 tsp smoked paprika
- 1 tsp thyme
- 1 tsp rosemary
- 0.5 tsp oregano
- 1 tsp salt
- 1 tsp black pepper
- 1 knob of butter
- Preheat your oven to 190C | 375 F.
- Peel your potatoes and slice them into thin slices with either a mandolin or a knife and chopping board. Get them as thin as possible (0.5cm)
- Wash your leek and halve it lengthways, cutting off the ends. Slice thinly and add to a pan with your butter.
- Saute the leeks for 3-4 minutes until softened, then add your minced grated and cook for another minute.
- Add the wine to the pan, followed by the cream and then the spices. Stir everything together and allow to simmer for 3-4 minutes or until the cream thickens.
- Tip in 3/4 of your grated cheese and stir it into the sauce. Remove the pan from the heat.
- Line your baking dish with a spoonful of the creamy leek mixture, then place your thinly sliced potatoes around the dish. Stacking them upright as pictured will get you maximum crispiness!
- Pour the rest of the creamy leeks over the potatoes, using your spatula to help the cream and leeks get between the gaps in the potatoes to fully cover them.
- Scatter over the remaining cheese, and then cover the dish with foil.
- Bake for 30 minutes, then remove the foil and bake for another 20 minutes until the top is golden and crunchy.
Get the potatoes sliced as thin as possible to maximum crispiness, and ensure they are even sizes so that they cook at the same time in the oven.
I find this dish most aesthetic when the potatoes are stacked upright, but you could also toss the potatoes in the creamy leek sauce and then pour the whole thing into your dish however the potatoes fall - they'll taste the same!
This dish does reheat beautifully. Just cover with foil to avoid the top burning and bake for 30 minutes or until the dish has warmed through.
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Nutrition Information:Yield: 5 Serving Size: 1
Amount Per Serving: Calories: 500Total Fat: 26gSaturated Fat: 16gTrans Fat: 1gUnsaturated Fat: 8gCholesterol: 78mgSodium: 625mgCarbohydrates: 56gFiber: 6gSugar: 5gProtein: 11g