Sweet Potato Quiche with Mascarpone Cheese

Preheat the oven to 300 degrees F (150 degrees C).

Add 2 tablespoons oil to a frying pan over medium heat. Cook sweet potatoes and salt until starting to brown 5 to 10 minutes adding more oil if necessary. Transfer to an 11 x 7-inch rectangular glass baking dish. Press sweet potatoes into the bottom to form a compact layer.

Add 1 tablespoon oil to the frying pan and cook onion over medium heat until translucent about 3 minutes. Add cooked mixed vegetables season with salt and pepper and cook until slightly browned 5 to 10 minutes. Transfer to the baking dish with the sweet potatoes.

Beat eggs in a blender until just blended then add mascarpone cheese. Beat until mascarpone cheese starts to separate into smaller bits about 1 minute more; it won't fully blend. Pour over the vegetables in the baking dish. Top with chopped scallions and mix them in slightly.

Bake quiche in the preheated oven until set and slightly browned 55 to 75 minutes.