In a large pot or Dutch oven, heat the olive oil over medium heat. Add the chopped onion and sauté until softened, about 5-7 minutes.
Add the minced garlic, dried oregano, and black pepper. Cook for another minute until fragrant.
Stir in the Arborio rice and toast it for 1-2 minutes, ensuring each grain is coated with oil.
Pour in the vegetable broth and bring to a simmer. Reduce heat to low, cover, and cook for 15-18 minutes, or until the rice is al dente and most of the liquid has been absorbed. Stir occasionally to prevent sticking.
Remove from heat and stir in the fresh lemon juice and salt. Taste and adjust seasoning as needed.
Let the rice stand, covered, for 5 minutes before serving. Garnish with fresh parsley and crumbled feta cheese, if desired.
Notes
This lemon rice is best served warm. It pairs well with grilled meats, fish, or vegetables.