01 - Preheat oven to 425°F (218°C) and line a large, rimmed sheet pan with parchment paper.
02 - Toss halved baby potatoes with 1 tablespoon olive oil, 1/2 teaspoon salt, and 1/4 teaspoon black pepper. Spread evenly on the sheet pan and roast for 15 minutes.
03 - In a bowl, mix broccoli florets and sliced bell pepper with remaining olive oil, salt, and pepper. Add to the sheet pan with potatoes, stir gently, and roast an additional 10 minutes.
04 - Whisk ranch dressing, lemon juice, lemon zest, smoked paprika, and cayenne pepper in a small bowl until smooth.
05 - Arrange salmon fillets on top of roasted vegetables. Brush each fillet generously with the prepared ranch glaze.
06 - Return sheet pan to oven and roast for 10–12 minutes, until salmon flakes easily and vegetables are tender.
07 - Transfer salmon and vegetables to plates and serve immediately with extra lemon wedges, if desired.