Easy Spanish paella

Name: Easy Spanish paella
Ingredients: 4 large boneless, skinless chicken thighs; 16 Headless prawns (in shell) (fresh or frozen); 16 - 20 mussels (in shell); 2½ ounces / 70 grams chorizo sausage (sliced); 2½ ounces / 70 grams calamari (sliced); 1 mediium onion (diced); 1 medium red pepper / capsicum (seeds removed and sliced); 2 medium tomatoes (diced); 1 tablespoon tomato puree/paste (optional); ½ cup frozen peas; 1 cup paella rice; 1 teaspoon chopped garlic; 3 cups chicken stock (you can make it with stock cubes); 1 pinch saffron (soaked in 1 tablespoon water); 1 teaspoon paprika; 2 tablespoons olive oil (for browning meat and onions); Salt and pepper (to taste); 1 small lemon for garnish (optional)