Place the stock and water in a sauce pan and bring to a boil over medium heat. Reduce heat to low and continue to simmer.

Heat 1 tablespoon olive oil in a large sauté pan over medium heat. Add the asparagus and cook until crisp tender, 3-4 minutes. Remove from pan and set aside.

Add the remaining 2 tablespoons of olive oil. Add the leek and cook until softened, about 2 minutes. Add the garlic and cook for 30 seconds longer. Add the arborio rice and toast in the pan, stirring constantly until toasted, 1-2 minutes..

Slowly add one ladleful (about 1/2 cup) of the warm stock, stirring the risotto frequently. Add an additional ladle full of stock each time the liquid has been absorbed, until all of the stock has been added and the risotto is al dente. The rice is ready for more stock when you can draw a line through the risotto with a wooden spoon and the liquid stays put.

Add the asparagus and fava beans to the risotto during the last minute of cooking.

Remove the risotto from heat and add the lemon zest, juice, parmesan cheese and butter, and season with salt and pepper to taste. Serve immediately and enjoy!