Cook the rice according to package directions.

Steam the carrots until tender but still firm.

Steam the red bell pepper until tender but still firm.

Steam the mushrooms until tender but still firm.

Steam the green peas until tender but still firm.

Place the cooked rice in a large bowl.

Add the steamed carrots, peppers, mushrooms, peas, celery, and parsley to the rice.

In a separate bowl, whisk together the olive oil, vegetable oil, lemon juice, garlic, and dill (or marjoram).

Pour the marinade over the rice and vegetable mixture.

Toss gently to combine.

Refrigerate for at least 20 minutes, stirring occasionally, to allow the marinade to flavor the rice.

Before serving, garnish with tomato wedges, green olives, and optional ingredients like dried currants or toasted pine nuts.