Preheat oven to 350 degrees F.
Lightly oil a 9-inch glass pie plate or 1 1/2 -quart casserole.
In large skillet, heat oil over medium heat. Add onion and sauté 5 minutes. Add mushrooms, oregano, thyme and 1/4 teaspoon salt. Sauté until mushrooms give up their liquid and become tender. Transfer mixture to large bowl.
Add carrot, zucchini, pecans, cheese, and couscous to bowl, stirring to mix. Beat together egg, water and remaining 1/4 teaspoon salt; stir into vegetable mixture until well combined.
Spread mixture evenly in pie plate. Cover tightly with aluminum foil and bake 30 minutes. Cool, covered, at least 30 minutes before serving.
Nutrition information per serving (1/6 of tart)-219 calories; 7g protein; 14g carbohydrate; 3g fiber; 16g fat; 3g saturated fat; 45mg cholesterol; 259mg sodium.