1. Heat the olive oil in a large skillet over medium heat. Add the chopped onion and garlic, and cook until softened.
2. Add the Arborio rice to the skillet and cook, stirring constantly, until the rice is lightly toasted.
3. Pour in the white wine and cook, stirring, until the wine is absorbed by the rice.
4. Begin adding the warm chicken broth, one cup at a time, stirring constantly and allowing each cup to be absorbed before adding the next.
5. When the rice is almost cooked, add the shrimp to the skillet. Cook until the shrimp are pink and opaque.
6. Stir in the butter and grated Parmesan cheese. Season with salt and pepper to taste.
7. Serve the risotto hot, garnished with additional Parmesan cheese if desired.