1. Combine couscous and water. Let stand until tender (5-10 minutes).
2. Heat oil in a small skillet over low heat. Add bell pepper, garlic, herbs, and spices. Cook, stirring, until the bell pepper is slightly softened (1-2 minutes).
3. Prepare a grill or preheat the broiler to high.
4. Mix turkey, couscous, and bell pepper thoroughly. Shape into four 3/4" thick patties. Grill or broil the patties, turning once, until they reach a minimum internal temperature of 165 degrees F (5 minutes per side).
5. Build burgers on buns with tomato and lettuce.