Preheat the oven to 180°C, peel and slice the sweet potatoes. I used a mandoline so all the pieces were evenly thick, but a knife does the job just as well. Coat the dish with butter, then cover the bottom of the dish with sweet potato slices. Cut the rest of the slices in half and fill around the edges, round sides upwards. When the dish is covered with the sweet potato slices, spread some olive oil, salt and pepper over. Bake the crust for 20 minutes.
Mince the onions. Heat a pan over medium heat, add the coconut oil and the onions. When the onions are golden, add the spinach and sauté for 3 minutes. Remove from heat and set aside.
In a bowl, whisk the eggs, rice milk, salt, pepper and paprika powder.
Spread the spinach and onion filling on the sweet potato crust. Add goat cheese pieces and pour the egg mixture all over.
Bake at 180°C for 35 minutes. Let the quiche cool for 5 minutes and ENJOY!