Step 1: Prepare the Scallops: Pat the scallops thoroughly dry with paper towels. Season them with 1 tsp salt, 1/2 tsp black pepper, and 1 tbsp lemon juice.
Step 2: Sear the Scallops: Heat a large skillet over medium-high heat and add 2 tbsp olive oil. Once hot, add the scallops in a single layer, ensuring not to overcrowd the pan. Sear for 2-3 minutes per side, or until golden brown and cooked through. Remove scallops from the skillet and set aside.
Step 3: Start the Risotto Base: In the same skillet (no need to clean), melt 2 tbsp unsalted butter over medium heat. Add the 1/2 cup diced onion and minced garlic, cooking until softened and fragrant, about 3-5 minutes.
Step 4: Toast the Rice: Stir in the 1 1/2 cups Arborio rice and cook for 1-2 minutes, stirring constantly, until the edges of the rice grains become translucent.
Step 5: Deglaze and Add Broth: Pour in the 1/2 cup dry white wine and stir until it's completely absorbed by the rice. Begin adding the warm vegetable broth, one ladleful (about 1/2 cup) at a time, stirring frequently. Allow each addition of broth to be mostly absorbed before adding the next.
Step 6: Incorporate Mushrooms and Finish Risotto: After about 15-20 minutes, when the risotto is nearly creamy and al dente, stir in the 1 cup sliced mushrooms. Continue adding broth and stirring until the risotto is creamy, the rice is tender with a slight bite, and the mushrooms are cooked. This typically takes 25-30 minutes total.
Step 7: Finish and Season: Remove the skillet from the heat. Stir in 1/2 cup grated Parmesan cheese and 1/4 cup chopped fresh parsley. Taste and adjust seasoning with additional salt and pepper if needed.
Step 8: Assemble and Serve: Divide the creamy mushroom risotto among serving plates. Top each portion with the seared scallops. Garnish with fresh parsley leaves and lemon wedges, if desired. Serve immediately and enjoy!