Prep everything first: dice the sweet potato, onion and tomato; slice the zucchini; mince the garlic; slice the green onions; pat the salmon and shrimp dry and season both lightly with 1/2 teaspoon salt and a few grinds of black pepper. Having mise en place is key for a paella-style dish because the cooking moves quickly once the rice and broth are added.

Roast the sweet potato for caramelized sweetness: Preheat oven to 425°F (220°C). Toss the diced sweet potato with 1/2 tablespoon olive oil and a pinch of salt. Spread on a sheet tray and roast 15–18 minutes until edges are golden and slightly crisp. Roasting concentrates the sweetness and prevents the cubes from becoming mushy when added to the skillet later.

Warm the broth and bloom the saffron (if using): In a medium saucepan, bring the chicken broth to a simmer. Stir in the turmeric and the saffron threads (if using) and let steep off the heat for 5 minutes. Warming the broth releases aromatics and keeps the rice cooking temperature steady when added to the skillet.

Sear the salmon and shrimp separately for texture: Heat a large 12-inch ovenproof skillet (or wide sauté pan) over medium-high heat. Add 1/2 tablespoon olive oil. Place salmon pieces skinless-side down and sear 1–2 minutes per side just to develop color (you want a light crust but not fully cooked—reserve). Transfer salmon to a plate. Add shrimp and sear 30–60 seconds per side until just opaque; remove and reserve. Quick searing gives seafood caramelized flavor and ensures it won’t overcook during the rice phase.

Build the flavor base: Reduce heat to medium and add the butter to the empty skillet. When butter melts, add the diced onion and sauté 4–5 minutes until translucent and beginning to brown at the edges—browning adds sweetness. Stir in the minced garlic and smoked paprika and cook 30 seconds until fragrant to bloom the spices and avoid raw garlic flavor.

Toast the rice briefly: Add the uncooked yellow rice to the skillet and stir to coat the grains in butter and oil. Toast 1–2 minutes—this step helps the rice absorb the broth evenly and adds a faintly nutty flavor. Toasting also helps prevent the rice from becoming gluey.

Add tomatoes and zucchini: Stir in the diced tomato and sliced zucchini and cook 1–2 minutes to warm and begin to break down the tomato. This contributes acidity and moisture which will balance the richness of the fish and butter.

Pour in the warm broth and simmer uncovered: Carefully pour the hot broth over the rice and gently stir once to distribute. Spread the rice evenly in the pan. Bring to a steady simmer over medium-high heat, then reduce heat to maintain a gentle simmer. Do not stir frequently—allowing the rice to sit undisturbed lets a thin crust (socarrat) form on the bottom, which is a classic paella characteristic.

Arrange seafood and roasted sweet potato on top: After 12–15 minutes of simmering (rice should be about 70–80% cooked and liquid mostly absorbed), nestle the seared salmon and shrimp into the rice and scatter the roasted sweet potato cubes on top. Tuck a few tomato pieces and zucchini slices over the fish to prevent direct heat and help them finish cooking gently. Cover the skillet with a lid or foil and cook 3–5 minutes more—this finishes the seafood through by gentle steam without overcooking.

Finish and rest: Remove from heat and let the skillet rest, covered, 5 minutes. The resting phase allows the juices to redistribute and the rice to finish steaming to tender perfection. Uncover and check seasoning—add remaining 1 teaspoon salt if needed and freshly ground pepper to taste.

Garnish and serve: Scatter sliced green onions over the top and squeeze fresh lemon wedges over each serving. Serve straight from the skillet for dramatic presentation, encouraging diners to scrape a bit of the crust from the bottom for that authentic socarrat bite.

Storage and gentle reheating: Leftovers keep 2–3 days refrigerated in an airtight container. Reheat gently on the stovetop with a splash of broth or in a 350°F (175°C) oven covered for 10–12 minutes to avoid overcooking the seafood.