Soak cedar plank in water for about 1 hour. Preheat grill on HIGH for 10 min. Char bell peppers over high flame until black all over, close in a paper or plastic bag and set aside to steam. Once cool enough to handle, scrape off charred skin, seed and chop peppers.
Arrange chicken on plank. Brush with olive oil and season to taste with salt, pepper and herbs, or your favorite blend. Reduce grill temperature to medium-low. Place plank on grill grate. Close grill lid.
Cook chicken until internal temperature reaches 165 degrees, about 45 min. Check by inserting quick read thermometer halfway into thickest part of meat. Remove plank, cover with foil and set aside to rest for 5-10 minutes.
Puree roasted bell peppers, transfer to a pan to warm, seasoning to taste with salt, pepper and herbs. Feel free to customize this sauce to taste – great with chèvre, parmesan, crushed red pepper, etc.
