Bring the stock to a simmer in a medium saucepan.
Heat 2 tablespoons oil over medium in a deep skillet. Cook the leek stirring frequently, until soft, 6 to 7 minutes. Add the rice and cook, stirring until the edges are translucent, 2-3 minutes. Add the wine and cook, stirring, just until evaporated.
Add 1/2 cup of stock and cook, stirring, until almost absorbed. Continue adding 1/2 cup of stock in this manner until the liquid is creamy and the rice is al dente, about 20 minutes total (you may not need to add all the stock). Add the asparagus with the last addition of stock, and peas about 1 minute before the risotto is done.
Remove from the heat and stir in the cheese, and remaining 1 tablespoon of oil. Season with salt and pepper. Top with scallions and additional cheese before serving.