Add the olive oil and butter to a large sauté pan, without turning on the stove.
Add the onions, peppers, garlic, carrots, rosemary and season with a pinch of salt and freshly ground black pepper.
Add the spices, smoked paprika, cumin seeds and turmeric. Turn on the flame, to medium. Stir and cook 4 to 5 minutes.
Add in the tomatoes, dijon mustard and stock. Stir to combine.
Add in the stock. stir. Bring to a quick boil over medium high heat.
Add in the red snapper. Spoon some of the vegetables and liquid all over the fish - covering them completely. Cover the pan with a tight lid. Turn off the stove.
Transfer the pan to the preheated oven. Bake 8 to 10 minutes or until the internal temperature of the fish reads 141F/61C-145F/63F degrees.
Remove the pan from the oven. Serve on it's own or on a bed of rice.