Wash and trim your asparagus. Then cut your asparagus into small strips, about 2 – 3 cm (0.78 inch – 1.18 inch) long. Set aside.
In a wide medium sized saucepan, saute 2 tablespoons of butter, and chopped onion, over medium heat, until the onions are lightly browned.
Add the cut fresh asparagus and cook for a further 1 to 2 minutes. See note 1.
Mix through the arborio rice and saute until lightly golden brown. This should take about 1 to 2 minutes.
Next, add the white wine and cook until almost all the liquid is gone from the saucepan.
Over low to medium heat, add about ½ cup (125 ml) of stock to the rice mixture. Gently stir the rice through the mixture constantly until almost all the liquid has absorbed.
Repeat until all the stock has been used up and the rice is soft and tender.
Remove rice from heat, mix through the grated parmesan cheese, lemon juice and lemon zest, remaining butter, and salt and pepper to taste.
Allow the rice to sit for 1 to 2 minutes with a lid on.
Serve, garnished with freshly chopped parsley, and a sprinkle of extra lemon zest if desired.