5 cups chicken broth
2 Tbsp unsalted butter
1 Tbsp olive oil
1/4 cup finely minced onion
1-1/2 cups arborio or carnaroli rice
1/2 cup freshly squeezed lemon juice, about 2 lemons
1/4 cup white wine
1 cup fresh peas or defrosted frozen peas
1/4 cup half-and-half (or 2 Tbsp butter)
1/3 cup grated Parmigiano-Reggiano cheese
Bring the broth to a steady simmer in a saucepan on top of the stove, or in the microwave.
In a heavy 4-quart pot, heat the butter and oil. Add the onion and cook until translucent. Add the rice, and stir to coat the grains. Remove pan from the heat; add lemon juice and wine, and stir (be careful, the liquid might splatter when it goes into the pan). Return the pan to the burner. When the liquid is mostly absorbed, begin adding stock, 1 cup at a time, waiting for each to absorb almost entirely before adding more.
When you add the final cup of stock, add the peas. When the liquid is almost absorbed, remove pan from heat and stir in the half-and-half or butter, and cheese. Serve hot.