01 - In a large saucepan, melt the butter with the olive oil over medium heat. Add the chopped onion and cook for 3 to 4 minutes until softened and translucent, stirring occasionally.
02 - Stir in the minced garlic and cook for 1 minute until aromatic.
03 - Add the orzo pasta to the pan. Stir constantly for 1 to 2 minutes until the orzo is lightly golden.
04 - Pour in the dry white wine, if using. Simmer until almost completely absorbed by the orzo.
05 - Add the warm vegetable broth one cup at a time, stirring frequently and allowing each addition to absorb before adding the next. Continue until the orzo is creamy and al dente, about 12 to 15 minutes. You may not use all the broth.
06 - Remove the pan from heat. Stir in the grated Parmesan, lemon zest, and chopped parsley. Season with salt and freshly ground black pepper to taste.
07 - Serve immediately, garnished with extra Parmesan and parsley if desired.