This Sweet Potato Gratin is damn delicious and you’ve got to try it! This comforting dish combines the sweetness of thinly sliced sweet potatoes with the subtle onion notes of leeks, all enveloped in a creamy blend of sour cream and heavy cream. Topped off with a golden layer of melted cheddar cheese, this gratin is simply out of this world. Let’s dive into the simple steps to create this delicious masterpiece.
Ingredients and Substitutions
Sweet Potato – use about half a pound per person. A large sweet potato like the one in the photo is one about one pound. Yes, you can totally use potatoes for this as well but make sure they are the non-starchy kind so they don’t become mush. Yellow potatoes or russet potatoes work best.
Leek – for some reason, leeks aren’t always available in Montreal but if you can get fresh where you live year-round always use fresh. Otherwise, use bagged like I did. Scallions or spring onions work great as well.
Cream – I use a combo of sour cream and heavy whipping cream to reduce the fat content a little. You can use double the amount of heavy whipping cream though and omit the sour cream if you’re not concerned about fat content.
Spices – keep it simple. Salt, pepper, and a dash of nutmeg are all you need.
Cheese – any melty cheese will work. My personal favorite is a mix of cheddar and Parmesan. Cheddar melts really well and Parmesan gives a nice golden color.
How To Make The Best Sweet Potato Gratin
Only six simple steps. 10 minutes of work, tops.
- Peel sweet potato – Here you can find my favorite vegetable peeler (affiliate link).
- Thinly slice sweet potato – Here you can find my favorite mandoline (affiliate link).
- Layer sweet potatoes and leek.
- Mix creams and spices.
- Pour mixture over sweet potato and leek slices.
- Put cheese on top and bake.
How to Store Leftovers
If you have leftovers (who are you even?!), you can store them in an airtight container in the fridge for up to 4 days.
You can also freeze the gratin in a freezer-friendly container. To defrost simply put it in the fridge overnight.
To reheat, I recommend either using a microwave or adding it to a pan with a lid on and heat on medium-low.
More Sweet Potato Recipes
If you are as big of a fan of sweet potato as me you are not only going to love this Sweet Potato Gratin but also any and all of these sweet potato recipes:
- Roasted Sweet Potato Salad
- Red Lentil Sweet Potato Soup
- Sweet Potato Breakfast Casserole
- Instant Pot Sweet Potato Curry
- The Best Sweet Potato Noodles
Sweet Potato Gratin
- 1 lbs sweet potato
- 1 small leek
- 1/4 cup sour cream
- 1/4 cup 35% whipping cream
- 1/2 tsp salt
- 1/4 tsp black pepper
- 1/8 tsp nutmeg
- 1/2 cup melty cheese - *
- 1 tsp chopped parsley
- Preheat oven to 400F.
- Peel and thinly slice sweet potato, and thinly slice leek.
- Layer sweet potato slices and leek slices in a casserole dish.
- In a small bowl whisk creams and spices together until well combined, then pour over sweet potatoes and leek.
- Top everything with grated cheese and bake for 45 minutes.
- Sprinkle with freshly chopped parsley and serve.
- Use low fat cheese if you want to keep it around 400cal per serving, and full fat to get closer to 500cal
- To reduce the fat content and calorie count even further you can use 10% or 15% cream instead or even milk but the sauce won’t be as creamy that way.