Begin by chopping all your vegetables, including bell peppers, onion, and garlic. Season the chicken generously with salt and pepper, ensuring every piece is flavored well.

In a skillet, heat olive oil over medium heat until shimmering. Add the chopped onion and minced garlic, sautéing for about 3-5 minutes until they become fragrant and translucent.

Transfer the sautéed onion and garlic mixture to the slow cooker. Add the seasoned chicken, chopped bell peppers, canned tomatoes, and Mediterranean herbs. Stir gently to combine.

Cover the slow cooker and set it to cook on low for 6-8 hours or on high for 3-4 hours.

Once cooked, taste and adjust the seasoning with salt and pepper. Serve warm, garnished with crumbled feta cheese.