In a large bowl, whisk eggs and cream together till combined.
Add bread cubes.
Cover and chill 1 hour.
In a medium skillet, cook the onion and red or green pepper in cooking oil till vegetables are tender, but not brown.
Add the zucchini and mushrooms; cook till zucchini is just crisp-tender.
Remove from heat.
Stir in salt, pepper, oregano and basil.
Stir into eggs with the artichoke hearts, shredded Gruyere cheese and 1/2 cup of the shredded cheddar cheese.
Pour into a 2-quart square (8x8x2-inch) baking dish.
Sprinkle with the remaining 1/2 cup cheddar cheese.
Bake in a 325° oven for 55 minutes or till mixture appears set when you shake it gently.
Remove from oven.
Let stand for 5 to 10 minutes.
Per serving: 2123 Calories (kcal); 157g Total Fat; (66% calories from fat); 145g Protein; 35g Carbohydrate; 1853mg Cholesterol; 2967mg Sodium Food Exchanges: 0 Grain(Starch); 19 1/2 Lean Meat; 5 1/2 Vegetable; 0 Fruit; 19 Fat; 0 Other Carbohydrates