01 - Heat the olive oil and 1 tablespoon butter in a large saucepan over medium heat. Add the onion and cook until translucent, about 3 minutes. Add the garlic and cook for 30 seconds until fragrant.
02 - Stir in the arborio rice and cook for 2 minutes, stirring constantly, until the rice grains are lightly toasted and translucent around the edges.
03 - Pour in the white wine and stir continuously until fully absorbed by the rice, about 1 minute.
04 - Add the warm vegetable broth one ladle at a time, stirring frequently and allowing each addition to be mostly absorbed before adding the next. Maintain a gentle simmer throughout.
05 - After 10 minutes of cooking, add the asparagus pieces. Continue adding broth and stirring, maintaining the creamy texture.
06 - When the rice is just tender and creamy (about 18–20 minutes total cooking time), stir in the peas, lemon zest, remaining butter, Parmesan cheese, and heavy cream if using. Cook for 2–3 minutes more until the peas are bright green and heated through.
07 - Season with salt and pepper to taste. Remove from heat, cover, and let rest for 2 minutes to allow flavors to meld.
08 - Serve hot, garnished with fresh parsley and additional Parmesan if desired.