Step 1: Preheat your oven to 400°F (200°C).
Step 2: In a large, oven-safe pot or Dutch oven (at least 3.5-quart capacity), heat the olive oil over medium heat. Add the chopped onion and cook for 3-4 minutes until softened and translucent.
Step 3: Add the minced garlic and cook for another minute until fragrant. Be careful not to burn the garlic.
Step 4: Stir in the rinsed rice, coating it with the oil and aromatics. Cook for 1-2 minutes, stirring occasionally.
Step 5: Pour in the chicken or vegetable broth. Add the dried dill, salt, and black pepper. Bring the mixture to a gentle simmer, then reduce the heat to low, cover the pot tightly, and cook for 15 minutes.
Step 6: While the rice is partially cooking, pat your salmon fillets dry with paper towels and season them with a little extra salt and pepper if desired.
Step 7: After 15 minutes, remove the pot from the heat (do not lift the lid). Carefully open the lid and nestle the salmon fillets on top of the rice. Arrange the asparagus pieces and halved cherry tomatoes around the salmon. If using, place lemon slices on top of the salmon.
Step 8: Cover the pot tightly again and transfer it to the preheated oven. Bake for 12-18 minutes, or until the salmon is cooked through and flakes easily with a fork, and the rice has absorbed all the liquid and is tender.
Step 9: Once cooked, carefully remove the pot from the oven. Keep the lid on and let the dish rest for 5-10 minutes. This allows the rice to steam further and the flavors to meld.
Step 10: Gently fluff the rice with a fork, being careful not to break up the salmon. Garnish with fresh parsley or dill, and serve immediately.