Heat chicken broth and water in a small saucepan.

Melt one tbsp butter with olive oil in a heavy bottomed saucepan.
Add onion and cook for 4-5 minutes until transparent.
Add rice and coat well in butter & onion.
Add white wine and let it be absorbed by rice, while stirring.

Using a ladle, add half a cup of heated chicken broth to the rice, and stir calmly over a medium heat.
Once broth is absorbed by rice, add another half cup of broth.
Keep the rice moving in the pan.
Add stock by the ladle only when the previous broth has been absorbed.
After about 20 minutes, start tasting the rice until the rice is cooked but not soft, and there is a creaminess to the sauce, neither soupy nor dry.

Turn off the heat, add salt & pepper to taste.
Stir in 1 tbsp butter and parmigiano and let rest for 5 minutes before serving.