Heat chicken stock in a large kettle nearly to boiling; reduce heat to low.
Heat 2 tablespoons butter and the oil in a large saucepan over medium heat; add onions and salt; sauté until the onions are translucent, ~6 minutes; add garlic; sauté ~30 seconds, until fragrant.
Add rice; increase to medium heat, stir constantly until rice looks is translucent and barely golden, ~5 minutes.
Add white wine; stir until the liquid has absorbed, ~2 minutes
Add 1 ladle of chicken stock; continue stirring until the rice has absorbed the broth; add the remaining broth 1 ladle at a time allowing the liquid to almost completely absorb each time; this process can take ~25 minutes.
Stir in remaining two tablespoons butter and Parmesan.
