Heat olive oil in a medium skillet over medium heat. Add garlic, onion, and bell pepper. Cook for a few minutes or until the onions have softened. Transfer to a large bowl to cool for a few minutes.
To make meatloaf less spicy and kid-friendly, omit red pepper flakes and hot sauce.
If you can't find ground chicken breast, you can ask the butcher to grind it for you at the grocery store - they always do this for me at whole foods. Another option is extra lean ground turkey!
Feel free to use 1 egg instead of 2 egg whites.