Warm broth in small saucepan; cover and set aside.
In a 2-quart saucepan, melt 4 tablespoons of butter over medium-high heat. Add the diced onion and sauté until translucent, about 4 minutes.
Add rice and cook 2-3 minutes, stirring constantly, until rice is opaque. Add the garlic and stir until fragrant, about 1 minute.
Add the white wine and cook, stirring, until absorbed.
Add 1/2 cup of broth to rice and stir continuously until absorbed. Continue adding 1/2 cup broth at a time, stirring continuously until absorbed after each addition. Continue until all broth has been added, about 20 minutes.
Add the Parmesan cheese, heavy cream, salt and pepper and stir to combine well.