In a saucepan, heat 2 tablespoons of olive oil over medium heat. Add the chopped onion and cook until translucent, about 5 minutes.

Add the minced garlic and sliced mushrooms, cooking for another 3-4 minutes until the mushrooms are tender.

Stir in the arborio rice and cook for 1-2 minutes until the rice is lightly toasted.

Gradually add the warm broth, one ladle at a time, stirring frequently until the liquid is absorbed before adding more. Continue until the rice is creamy and al dente, about 18-20 minutes.

Stir in the butter and Parmesan cheese, and season with salt and pepper to taste. Keep warm.

Pat the scallops dry with paper towels and season with salt and pepper on both sides.

In a skillet, heat 2 tablespoons of olive oil over high heat until shimmering.

Add the scallops in a single layer, making sure not to overcrowd the pan. Sear for about 2-3 minutes on each side until golden brown and cooked through.

Remove the scallops from the skillet and let them rest for a minute before serving.

Plate the mushroom risotto and top with the seared scallops. Garnish with additional Parmesan if desired.