Heat the vegetable broth in a medium saucepan over low heat and keep it warm throughout the cooking process. This ensures the rice cooks evenly.

In a large heavy-bottomed pan or Dutch oven, heat the olive oil and 1 tablespoon of butter over medium heat. Add the diced onion and cook for 4-5 minutes until softened and translucent, stirring occasionally.

Add the arborio rice to the pan and stir constantly for 2-3 minutes until the grains are lightly toasted and coated with the oil. The edges should become slightly translucent.

Pour in the white wine and stir until completely absorbed. Begin adding the warm broth one ladle at a time, stirring frequently and allowing each addition to be absorbed before adding the next. Continue this process for about 18-20 minutes until the rice is creamy and tender but still has a slight bite.

When the rice is almost done, stir in the peas and cook for an additional 3-4 minutes until the peas are tender and heated through.

Remove the pan from heat and stir in the remaining 2 tablespoons of butter, Parmesan cheese, lemon zest, lemon juice, and chopped mint. Season with salt and pepper to taste. Stir vigorously to create a creamy consistency.

Serve the risotto immediately in warm bowls, garnished with additional Parmesan cheese, fresh mint leaves, and a drizzle of olive oil if desired.