Add the broth to a saucepan and keep it warm over low heat.

Heat the olive oil and 1 tablespoon of butter in a large skillet or wide saucepan over medium heat. Add the shallot and cook for 3 to 4 minutes, until softened.

Add the garlic and cook for 30 seconds.

Stir in the Arborio rice and cook for 1 to 2 minutes, stirring frequently, until the grains are lightly toasted.

Pour in the white wine and cook until it is almost completely absorbed.

Add about 1 cup of the warm broth. Stir frequently until the liquid is mostly absorbed.

Continue adding the broth about 1/2 to 1 cup at a time, stirring often and allowing each addition to absorb before adding more. Continue for about 18 to 22 minutes, until the rice is creamy and tender but still slightly firm in the center.

Stir in the pumpkin puree, thyme, nutmeg, salt, and pepper. Cook for another 2 to 3 minutes, adding a splash of broth if the risotto becomes too thick.

Remove the pan from the heat. Stir in the Parmesan, remaining tablespoon of butter, and sage, if using.

Taste and adjust the seasoning. Serve immediately with extra Parmesan on top.