Combine heavy cream and half of lemon zest in a bowl. Whisk cream to soft peaks. Set aside.
In a saucepan, bring chicken stock and 2 cups of water to a simmer.
Mince onion (it should be smaller than the rice).
In a wide pan, heat oil on medium-low heat. Add onion and 1/4 teaspoon salt. Cook and stir until onion is soft but not brown, about four minutes.
Add arborio rice and 1/2 teaspoon salt. Cook and stir for three minutes. Rice should remain white.
Raise heat to medium. Add wine. Cook and stir until the rice has absorbed the liquid.
Add 1/2 cup of stock. Cook and stir until the rice has absorbed all the stock and the pan is mostly dry.
Continue adding stock, 1/2 cup at a time, cooking and stirring until rice has absorbed liquid before adding more.
Once all of the liquid has been added, test the risotto for doneness. If it is still firm, add more water until the desired texture is reached.
Add remaining lemon zest and stir.
Remove from heat, stir in butter and parmesan. Stir continuously. When butter is incorporated into the risotto, fold in the heavy cream. Taste and adjust salt if needed.
Finish by stirring in half a teaspoon of lemon juice. Top with parsley and basil.
