Follow these detailed steps to ensure your One-Pan Lemon Garlic Fish and Rice comes out perfectly every time. The process is straightforward, designed for ease without sacrificing an ounce of flavor.

Step 1: Prepare the Oven and Pan
Preheat your oven to 400°F (200°C). Select a large, oven-safe skillet or a 9×13 inch baking dish. A pan with high sides is ideal for containing the rice and broth.

Step 2: Build the Flavor Base for the Rice
Place your oven-safe skillet on the stovetop over medium heat (if using a baking dish, perform this step in a separate skillet and then transfer). Add the 2 tablespoons of olive oil. Once shimmering, add the finely chopped yellow onion and sauté for 3-4 minutes until it becomes soft and translucent. This step is crucial as it mellows the onion’s raw bite and builds a sweet, aromatic foundation.

Step 3: Toast the Rice and Add Broth
Add the uncooked long-grain white rice to the skillet with the onions. Stir constantly for about 1 minute, toasting the grains. This process gives the rice a slightly nutty flavor and helps the grains remain distinct after cooking. Pour in the 3 cups of chicken or vegetable broth and bring the mixture to a gentle simmer on the stovetop.

Step 4: The Initial Bake
Once simmering, turn off the heat. Carefully cover the skillet or baking dish tightly with a lid or heavy-duty aluminum foil. This is critical for trapping the steam needed to cook the rice. Place the pan in the preheated oven and bake for 15 minutes. During this time, the rice will begin to absorb the flavorful broth.

Step 5: Craft the Luscious Lemon Garlic Sauce
While the rice is having its initial bake, prepare the sauce. In a small bowl, whisk together the melted butter, minced garlic, the zest and juice of one lemon, dried oregano, salt, black pepper, and optional red pepper flakes. Whisking ensures all the elements are well combined, creating a cohesive and powerful sauce. The aroma alone will tell you you’re on the right track.

Step 6: Prepare the Fish
Take your fish fillets and pat them thoroughly dry with paper towels on all sides. This step is non-negotiable for achieving a beautiful texture. Excess moisture will steam the fish, preventing it from flaking nicely. Season both sides of the fillets generously with additional salt and pepper.

Step 7: Combine and Bake to Perfection
After the initial 15 minutes of baking, carefully remove the pan from the oven. The rice should have absorbed most, but not all, of the liquid. Gently fluff the rice with a fork. Now, nestle the seasoned fish fillets into the rice. Scatter the halved cherry tomatoes around the fish. Drizzle the entire dish—fish, rice, and tomatoes—with the prepared lemon garlic butter sauce, ensuring the fish is well-coated.

Step 8: The Final Bake
Place the pan back into the oven, uncovered. Bake for an additional 12-15 minutes. The exact time will depend on the thickness of your fish fillets. The dish is ready when the rice is tender and has absorbed all the liquid, and the fish is opaque and flakes easily with a fork. If you insert a fork into the thickest part of a fillet and gently twist, it should break apart into beautiful, moist flakes.

Step 9: Rest and Garnish
Remove the pan from the oven. Let it rest for 3-5 minutes. This allows the fish to finish cooking gently in the residual heat and helps the juices redistribute, resulting in a more tender and flavorful final product. Just before serving, sprinkle generously with freshly chopped parsley and serve with extra lemon wedges on the side for squeezing.