Here's a classic Valencian seafood paella:

Ingredients (4 servings)
- 300g bomba rice (or arborio)
- 200g shrimp, 200g mussels, 150g squid rings
- 1 onion, 4 garlic cloves, 1 red pepper — diced
- 200g crushed tomatoes
- 1L fish/seafood stock (warm)
- 1 tsp smoked paprika, 1/2 tsp saffron threads
- Olive oil, salt, pepper
- Lemon wedges, fresh parsley

Steps
1. Bloom saffron in 2 tbsp warm stock for 10 min
2. Heat olive oil in a wide pan (paellera ideally), sear shrimp & squid 2 min per side — set aside
3. Sauté onion, pepper, garlic until soft (~5 min)
4. Add paprika, stir 30 sec, then crushed tomatoes — cook down 5 min
5. Pour in rice, stir to coat, then add warm stock + saffron
6. Don't stir anymore — cook medium heat 18-20 min
7. Nestle mussels into rice at 10 min mark, add shrimp & squid back at 15 min
8. When liquid is absorbed, crank heat 2 min for the socarrat (crispy bottom)
9. Rest 5 min covered with a towel, serve with Lemon

The secret: the socarrat is everything — that caramelized crust at the bottom is what separates good from great paella. And never stir the rice once the stock is in.