Pre-heat the oven to 350F. Use a paper towel to apply a thin coating of oil to a 9-½ inch glass pie dish. Peel the sweet potato then slice into uniform slices a hair thicker than ⅛ inch each.

Cut ¼ inch off the widest slices to create a flat bottom. Arrange the slices like flower petals against the side of the pie dish, overlapping slightly. Do this until you have two layers of sweet potato petals. Arrange the remaining slices in two layers on the bottom of the pie dish, use the cut pieces to fill in spaces. There will be gaps, lumps, and bumps – don’t worry this is all fine.

Spray the assembled crust with a touch of oil or cooking spray and sprinkle with a pinch or two of salt then bake for 20 minutes.

Add oil to a large skillet over medium heat. When the oil is warm add the chopped onion and a pinch of salt. Let cook until the onions begin to brown and the natural sugars caramelize, stir frequently. Remove the caramelized onions from the pan and set aside. Whisk together the eggs, egg whites, milk, mustard, salt and pepper then set the mixture aside.

Allow the crust to cool slightly then gently adjust the sweet potato slices as needed to fill in any large spaces that may have been created during cooking.

Increase the oven temperature to 375F.

Spoon the onions into the crust in an even layer, sprinkle over the blue cheese crumbles then top with the ham cubes. Pour the egg mixture over everything then bake for 35-40 minutes. The finished quiche will move slightly at the center when wiggled but should look firm.

Cool to room temperature before serving.