Cheesy Potato and Sweet Onion Gratin
Cheesy Potato and Sweet Onion Gratin is a satisfying, rich and creamy potato dish that will make you feel nurtured and loved. It’s brimming with potatoes and cheese balanced by the perfect amount of sweet caramelized onions which are enhanced by fresh herbs and white wine (if you choose to go the whole nine yards). Each forkful is a layered delight.
Jump to RecipeIngredients
Organize the ingredients – potatoes, cheese (brie and/or gruyere, parmesan), Brie or Gruyere (not photographed) and Parmeson, 1-2 onions, fresh herbs (sage, thyme, and/or rosemary), white wine (optional), and heavy cream.
Cooking the Onions
Cut the onions in half vertically through the root and then use a mandolin to thinly slice the onions into half moons. Heat olive oil in a large pan over medium heat. Add onions, fresh herbs, and season with kosher salt and freshly ground pepper. Stir occasionally and cook until onions are caramelized, approximately 15 mins. For added flavor, add 1/2 cup white wine and cook for an additional 5 mins until wine has evaporated, optional.
Slicing the Potatoes
While onions are cooking, slice the potatoes into rounds, preferably using a mandolin, otherwise slice as thinly as possible by hand. Cover the potatoes with a damp cloth or paper towel to keep them from browning.
Assembly
Lightly butter the baking dish. Start by placing one-third of the potato slices into the pan slightly overlapping them until bottom of dish is covered. Next, add half of the sautéd onions. Then scatter one cup of grated gruyére cheese on top or a couple of slices of Brie followed by drizzling 2 tablespoons of heavy cream. Season with kosher salt and pepper. Repeat this…1/3 potatoes, remainder of sautéd onions, one cup grated gruyére cheese or a few slices of Brie, and 2 tablespoons heavy cream. Finish assembly with remaining one-third of potatoes topped with final 1/2 cup of grated gruyére cheese and 1/4 cup of Parmesan. (If using the Brie throughout, it will not be used in this last step.) Season with more kosher salt and ground pepper and drizzle with olive oil.
Baking
Cover with foil and place in a pre-heated 350 degree oven. Cook covered for one hour. Increase oven temperature to 425 degrees and remove the foil. Cook uncovered for an additional 1/2 hour. Total cooking time is 1 1/2 hours.
Cheesy Potato and Sweet Onion Gratin
Let gratin rest for 5 minutes and then serve.
Cheesy Potato and Sweet Onion Gratin
Equipment
- Mandolin
- 7" x 10" or 9" x 9" Baking Dish
Ingredients
- 4 tablespoons olive oil divided
- 2 large sweet onions such as vidalia cut in half lengthwise through the root, sliced thinly with a mandolin or by hand
- 1/2 cup white wine optional (wine you would drink!)
- 2 tablespoons fresh herbs – sage, thyme, rosemary rough chopped
- 3-4 large russet potatoes peeled, sliced into rounds using a mandolin, otherwise slice as thinly as possible by hand. See NOTES below.
- 2 1/2 cups Gruyere and/or Swiss, shredded (Trader Joe's has a pre-packaged shredded Gruyere/Swiss mix that is amazing) or a wedge of Brie, sliced (other cheeses that melt easily can be used)
- 4 tablespoons heavy cream divided
- 1/4 cup parmesan cheese grated
- Kosher salt and pepper to season the potatoes and onions
- pat of butter salted or unsalted to grease the baking dish or cast iron pan
Instructions
- Heat 2 tablespoons olive oil in a large pan over medium heat. Add onions, fresh herbs, and season with kosher salt and freshly ground pepper. Stir occasionally and cook until onions are caramelized, approximately 15 mins. For added flavor, add 1/2 cup white wine and cook for an additional 5 mins until the wine has evaporated, optional.
- While onions are cooking, slice the potatoes. Cover the potatoes with a damp cloth or paper towel to keep them from browning.
- Preheat oven to 350 degrees.
- Once onions are cooked and potatoes are sliced, it’s time to assemble the dish. Lightly butter the baking dish. Start by placing one-third of the potato slices into the pan slightly overlapping them until bottom of dish is covered. Next, add half of the sautéed onions. Then scatter one cup of grated gruyere cheese on top or a couple of slices of Brie followed by drizzling 2 tablespoons of heavy cream. Season with kosher salt and pepper.
- Repeat…one-third of potatoes, remainder of sautéd onions, one cup grated gruyere cheese or a couple of slices of Brie, and 2 tablespoons heavy cream.
- Finish assembly with remaining one-third of potatoes topped with final 1/2 cup of gruyere cheese and 1/4 cup of Parmesan. (If using the Brie throughout, it will not be used in this last step.) Season with kosher salt and finish by drizzling remaining two tablespoons of olive oil on top. Cover gratin with foil.
- Place dish on middle rack in the oven and cook for 1 hour covered. Then remove foil, raise oven temperature to 425 degrees and continue cooking uncovered for and additional 1/2 hour. Total cooking time is 1 1/2 hours.
- Let gratin rest for 5 minutes and then serve.
Notes
Recipe by Giallozafferano.com that was found on Instagram at GialloZafferano Loves Italy.
If you like this recipe, you may also like these GFchow recipes. Cheesy, Crunchy Squash Gratin, Eggplant Gratin, and Smashed Thyme Potatoes with Aioli and Balsamic Syrup.
GLUTEN FREE DISCLAIMER
The recipes you find here are considered by me to be gluten free. However, it is up to you to make sure the ingredients you use are gluten free. Whenever possible, I will list specific brands of ingredients that I use, but always be sure to check the labels yourself to verify the item is gluten free.
