Heat oil in deep sauté pan over medium heat. Add in curry paste and cook until smooth consistency, about 3 minutes.

Add in onion and cook until translucent, 3-5 minutes.

Add garlic and cook for one more minute.

Add fish and cook another minute.

Pour in both cans of coconut milk, add salt and pepper and cook until milk is heated through, stirring gently occasionally, 3-4 minutes.

Add in broccoli and peppers and bring to boil.

Stir in cilantro and brown sugar, cover and turn down to simmer until veggies are crisp tender.

Turn off heat and add fish sauce, stirring gently until combined.

Serve immediately.