In a small pot, bring vegetable stock to a boil. Stir in freekeh and simmer, covered, for 20 minutes. Remove from heat and let it rest, covered, for 10 additional minutes.
In a sauté pan, heat first listed oil and add onion, celery, carrot and bell pepper. Cook until vegetables are soft. Add garlic and cook for 2 additional minutes.
In a medium mixing bowl combine the freekeh, vegetables, panko, mozzarella, egg, thyme and smoked paprika. Season with salt and pepper. Thoroughly mix the ingredients by hand until they begin to form a paste. Form 5-oz. patties.
In a sauté pan, heat second listed oil and cook the patties to a golden brown, flipping halfway through, about 4 minutes per side. Serve immediately on toasted wheat buns with lettuce and tomatoes.