Step 1

Preheat an outdoor grill for high heat and lightly oil the grate.

Step 2

Rub each trout generously with olive oil and sprinkle with sea salt; sprinkle inside of cavities with salt and black pepper. Place half the lemon and onion slices into cavity of each trout, along with minced garlic, and place a sprig of rosemary and thyme into cavities.

Step 3

Turn preheated grill down to low and place the trout directly onto the grill; cook until flesh flakes easily and the skins are browned, 6 to 7 minutes per side, flipping once.