In a saucepan, heat the vegetable broth over low heat and keep it warm.
In a large skillet, heat the olive oil and butter over medium heat. Add the chopped onion and sauté until translucent, about 3-4 minutes.
Add the minced garlic and cook for an additional minute, being careful not to burn it.
Stir in the Arborio rice, allowing it to toast slightly for about 2 minutes until it becomes slightly translucent.
Begin adding the warm broth, one ladle at a time, to the risotto. Stir continuously and wait until the liquid is mostly absorbed before adding the next ladle. This process will take about 18-20 minutes.
Once the rice is al dente and creamy, remove it from the heat. Stir in the heavy cream, grated Parmesan cheese, lemon juice, and lemon zest. Mix until everything is well combined and creamy.
Season with salt and pepper to taste.
Let it rest for a few minutes to allow the flavors to meld.
Notes
Serve in shallow bowls with chopped parsley and a lemon wedge.