Heat olive oil in a large skillet over medium heat.
Add the onions, peppers, and garlic and cook until the onion is translucent (about 3-4 minutes)
Add diced tomatoes, bay leaf, smoked paprika, salt, pepper, and saffron. Add white wine and cook for about 10 minutes.
Add the rice and parsley to the pot, and stir well.
Smooth the rice into an even layer in the pan then add the broth. Do not stir the rice again until serving.
Bring the mixture to a boil, then reduce to a simmer over medium-low heat. Gently shake the pan a few times while cooking to evenly distribute the broth. Don't stir the rice as you want it to get caramelized and toasted while cooking. The crispy toasted crust on the bottom is called socarrat and is part of the "secret" of making a good paella.
Cook for 15 - 18 minutes uncovered over medium low heat. While there is still broth on the top and the rice is cooked through, add the shrimp, mussels, scallops and clams into the rice so that it is nestled for cooking. Season the seafood with salt and pepper and cover the paella with a lid or foil to steam the mussels, clams and help the seafood cook through. This could take anywhere from 5 - 10 minutes.
Add the peas and fresh lemon juice and zest. Cook for an additional minute to heat the peas. Cover and let the paella rest for about 10 minutes off the heat before serving.
Top with fresh chopped parsley and lemon wedges.