Place heat diffuser on burner and place bottom of tagine on diffuser.
Turn burner to medium heat.
Coat bottom of tagine with olive oil and add onions.
Heat onions until they start to turn translucent.
Place chicken breasts in bottom of tagine, sprinkle with herbs, spices, salt and pepper, and cover. Cook for about 10 minutes, flip chicken and cook for another 5 minutes, covered.
Add vegetables, water, and additional herbs and spices, if desired.
Cover and continue to cook for 35-45 minutes or until vegetables are tender.
Remove chicken breast and cut into pieces. Mix vegetables, and return chicken to the mixture.
Serve and enjoy!