Dice the onion and slice the bell pepper.

In a skillet, heat the olive oil over medium heat.

Add the onion and bell pepper, sautéing for about 5 minutes until they start to soften.

Add the minced garlic, oregano, basil, salt, and pepper to the skillet and stir for 1 minute until fragrant.

Transfer the sautéed vegetables to the bottom of the crockpot.

Place the chicken breasts on top of the vegetables.

Pour the crushed tomatoes over the chicken.

Cover the crockpot and set it to low heat for 6 hours.

Once cooked, shred the chicken directly in the crockpot using two forks.

Stir in fresh parsley before serving.