You know how the old saying goes that “presentation is everything”? Well, when it comes to presenting a meal, I wouldn’t say that looks are EVERYTHING… but this is one beautiful way to present a potato side dish to those you love and want to impress. And how it looks is just the start of what’s great about Upside Down Potato and Onion Tart. Baking the dish in a hot oven helps to caramelize the top, or what will become the top, of the potato and onion tart. Fresh thyme adds an earthy quality and three different kinds of cheese combine for a complex bite, and let’s not forget a touch of garlic to finish it off.
You can dress this up or pare it down with extra or less cheese, and you can even leave the onions out… though why you would do that, I can’t imagine. The recipe as written uses Parmesan, feta and mozzarella, but you can use whatever combination you like. If you REALLY love cheese, then dare to double it.
We prefer it light on the cheese, but with healthy doses of black pepper and garlic. Add some crushed red pepper flakes or rosemary depending on the main dish or different seasons throughout the year. You can add chives and bacon, then serve sour cream on the side for a kind of loaded baked potato tart. Use your imagination with this recipe. How ever you customize it, the basics for putting everything together is to layer it like so:
Starting with a little butter and olive oil, saute the onions and fresh thyme leaves to get things started:
Meanwhile, slice those potatoes really thin (you could use red potatoes if you like) and then add the cheese, garlic, salt, pepper, extra thyme and diced onion:
Layer the potato mixture in the skillet, beginning from the outside and filling it in as you go, making sure not to leave any of the cheese behind in the bowl:
Now this just goes in the oven until the bottom, soon to be top, gets golden brown and crunchy.
When the tart is flipped over on the serving platter, some of the onions or potatoes might stick to the pan. Just scrape them off with a spatula and place them back on the tart. This usually happens to me when I’m trying to get the potatoes extra crispy or when I don’t add a lot of cheese because the cheese is kind of the glue for holding everything in place. Upside Down Potato and Onion Tart will look beautiful once it’s all put together, ready for an impressive presentation. This is one side dish that will present well and taste even better!
Cook's notes: When flipping the tart over onto your serving platter, some of the onions and potatoes may stick to your pan. Just have a spatula ready and carefully scrape them off the pan and place them back where they belong on the tart.
If you really like cheese, this tart can be made with any favorite cheeses you have on hand and I've made it with double the mozzarella and have used cheddar in place of the Parmesan. Experiment to your own liking.
- 1 tablespoon olive oil
- 2 tablespoons butter
- 1 tablespoon fresh thyme leaves, stripped from the stems, chopped if desired
- 1 large onion, sliced about ¼-inch thick
- 4 large russett potatoes, scrubbed, washed and sliced very thinly
- 2 tablespoons olive oil
- ¾ cup grated Parmesan cheese
- ¾ cup crumbled feta
- ¾ cup grated mozzarella
- 1 or 2 cloves garlic, minced
- 1 teaspoon sea salt
- 1 teaspoon freshly grated black pepper
- Preheat oven to 400F degrees. Melt the butter in a 12-inch non-stick skillet or well seasoned cast iron skillet over medium heat. Add the thyme and about 5 slices of the onion (reserve the remaining slices), placed equally around bottom of the skillet. Cook for 5 minutes, until onion begins to soften. Do not stir. You are making a design for the top of the tart.
- In a large bowl, place the sliced potatoes, 2 tablespoons olive oil, Parmesan, feta, mozzarella, garlic, salt and pepper. Toss to combine.
- You should have several slices of the onion left. Chop these and add to the potato mixture. Mix again.
- Layer the potato slices on top of the onion slices and continue in layers until the pan is full. You may need to add the cheese that doesn't adhere to the potatoes between the layers as you go.
- Cover the skillet with aluminum foil and bake in oven for 20 minutes.
- Remove aluminum foil and bake an additional 20-25 minutes, until the potatoes are golden.
- Take skillet out of the oven and let rest for 10 minutes.
- Using a serving plate that is larger than the diameter of the skillet, carefully invert the tart onto the plate (using hotpads). If some of the potatoes and/or onion sticks to the skillet, no worries - just scrape them off using a spatula and place back where they belong on the tart.
- Sprinkle with additional thyme leaves and black pepper.
- Optionally, grate more cheese on top or sprinkle with crushed red pepper flakes before serving.