Preheat oven to the broiler setting.
In a foil-lined cookie sheet place the fish skin side down, season with salt and pepper.
Top each filet with ¼ of the pesto sauce and some of the Brussels sprouts.
Arrange the tomatoes on the same tray then broil until golden brown and fully cooked, approximately 10 minutes.
Remove from the oven and let rest for a few minutes.
To serve, plate each filet separately with a few tomatoes, then garnish with parsley and chives.