
Preheat the oven to 400F/200C. Heat the oil in a 10-inch oven-safe skillet over medium heat. Add the leek and saute for 3-4 minutes.
Then add the asparagus and saute another 1-2 minutes.
Then add the frozen peas, baby spinach, salt and pepper, and saute another 1-2 minutes, or until the spinach is wilted. Remove 1/3 of the vegetables to a plate (optional, but it makes for a prettier frittata), and make sure the remaining half of vegetables is evenly spread out.
In a large bowl, whisk the eggs, yogurt, salt and pepper. Pour the eggs over the half of the vegetables in the pan. Cook on the stove for 2-3 minutes.
Add the remaining vegetables on top, then dollop with the goat cheese. Transfer to the oven and cook for 15-20 minutes, or until the eggs are set.
Garnish with additional herbs before serving.