Place chicken broth in a small sauce pan and bring to a simmer.
Trim woody ends off asparagus and rinse well. Chop asparagus in 1 inch pieces, separating the stems from the tips and set aside.
In a large dutch oven, heat oil on medium heat and sauté onion until translucent. Add rice and stir until it is coated with the oil and lightly toasted, about 2 minutes. Pour in the wine and cook until it has evaporated.
Begin adding hot broth to your rice mixture with a ladle, one scoop at a time, and stir. When the broth has been absorbed, continue adding broth, one ladle full at a time.
After about ten minutes of cooking, add the chopped asparagus stems. Continue adding broth as before. After five more minutes, add asparagus tips to the rice mixture.
Continue cooking until the rice is tender but still has some bite to it. Total cooking time may vary from 20-25 minutes. Add salt to taste.
Remove from heat and stir in lemon rind, lemon juice, grated Parmigiano cheese and butter. Serve immediately with extra Parmigiano at the table
Notes
The key to cooking risotto is to make sure your broth is hot. Keep your pot of broth simmering on the stove top next to your risotto pot.
For a vegetarian version, simply swap out vegetable broth for chicken broth.
The broth must be added a bit at a time and more is added when the broth has been absorbed by the rice. A good trick I learned is to drag a wooden spoon across the bottom of the pot. If you leave a space as you drag the spoon, you know it's time to add more broth.
After about 20 minutes of cooking, taste your rice to see if it's almost ready. It should be tender but with some bite to it. If you have run out of broth and your rice is not completely cooked, just add some water but make sure to heat it first.