The sweetness of the sweet potatoes is balanced by the creaminess and fragrance of the blue cheese in this sweet potato quiche. Seasoned with a little nutmeg and and ginger and topped with some freshly grated romano? This crustless quiche is absolutely phenomenal!
Meanwhile, slice the sweet potatoes. You want them uniformly sliced at about 1/8 inch thick.
Very lightly coat a baking dish with olive oil.You want the least amount of oil necessary to keep the sweet potatoes from sticking. Too much oil will transfer to the egg custard and that's not what you're looking for in a quiche!
Arrange the sweet potatoes along the bottom of the baking dish.
Lightly coat with olive oil and sprinkle with a dash of salt and pepper.I use an olive oil spritzer to do this, which is really a glorified spray bottle filled with olive oil. Although any light coating to keep the sweet potatoes from burning will do!
Roast in the oven for 20-25 minutes, or until the sweet potato is barely tender.You should be able to stick a fork in them with ease. Although you will still cook for another 45 minutes, so they should be tender, but not soft.
Let cool slightly.You don't want to add the eggs directly to a hot pan or the egg will scramble. It doesn't need to be cool to the touch, but you do want a slow bake! If it sizzles when you add the custard, it's too hot.
Cook Quiche
Reduce heat to 350 degrees Fahrenheit.
Once the sweet potato is cooled slightly, add the blue cheese and grated gruyere.
Whisk eggs, milk together, nutmeg, and ginger together. Pour into the baking dish.Dab any oil that rises to the surface. The excess oil from roasting the sweet potatoes will separate and float to the top.
Bake for about 45 minutes, or until the edge is firm, but the center still jiggles slightly.
Remove from oven and let set for 15 minutes. Serve immediately or refrigerate.Quiche is a great recipe to make ahead of time. It keeps well in the fridge and is delicious at room temperature or slightly warmed.
Tips, Tricks, & Notes
If you do a crust, you can use a tart pan. Which is the more traditional way to make quiche. I prefer a crustless quiche, though. And that means pouring the egg custard directly into the pan. This means that you do need a pie pan or other enclosed baking dish! Mine is a festive pumpkin shape, but that's just because I'm a sucker for kitsch.
I also have an entire article on The Fundamentals of Crustless Quiche with more tips and tricks on whether or not you want a crust, whether or not you need dairy or cheese, the type of pan to use, and a recommendation of toppings.