Peas and Cheese Tortellini

In a large saucepan of boiling, salter water, cook the tortellini until al dente; drain. Meanwhile, add the peas, butter and scallion whites to another large saucepan and cook over medium heat for 2 minutes. Whisk in the flour and cook, stirring, for 1 minutes. Gradually whisk in the milk and bring to a boil, stirring constantly. Stir in the scallion greens and season with salt and pepper. Stir the tortellini and cheese into the sauce. Divide the past among 4 serving bowls and sprinkle with more cheese.