How to Make It
Heat oil and butter in a large heavy saucepan. Add shallots and sauté over medium heat until shallots are tender, about 2 minutes.
Add rice and stir until all grains are coated and slightly translucent, about 2 minutes. Add Champagne and stir over medium high heat until all liquid is absorbed.
Add about 1 cup of hot broth to rice and stir constantly until almost all the broth is absorbed. Continue to add hot broth, one cup at a time, stirring until liquid is absorbed, before adding more broth. Use enough broth to cook the rice until it is just al dente.
Remove from heat and stir in Parmigiano-Reggiano. Serve immediately.