Pea Tortilla with Mint and Yogurt

Preheat the broiler. In a large, ovenproof, nonstick skillet, melt the butter. Add the peas and cook over moderate heat until warm, about 3 minutes. In a large bowl, beat 1/2 cup of the yogurt with the eggs, mint, salt and pepper until smooth. Pour the eggs over the peas and cook over moderately high heat until set on the bottom and around the edges, about 4 minutes. Transfer the skillet to the oven and broil 6 inches from the heat for about 3 minutes, until the top of the tortilla is set and lightly golden in spots. Slide the tortilla onto a plate, cut into wedges and serve with the remaining 1 cup of yogurt.