Preheat oven to 350F.
Heat the garlic oil in a large oven-safe skillet over medium-high heat.
Add chicken, season with salt and pepper and sear for 5 minutes, or until golden brown.
Add the smashed garlic cloves to the pan and flip the thighs over; continue to cook for 3 minutes, or until garlic is a little browned.
Remove chicken and garlic from skillet and set aside.
Place skillet over medium-high heat and heat 1 teaspoon garlic oil.
Add onions to skillet and cook for 2 minutes.
Add peppers, tomatoes, lemon slices and fresh parsley.
Season with salt and pepper and continue to cook for 5 minutes, or until onions are tender.
Arrange the chicken skin-side-up over the vegetable mixture.
Add the smashed garlic and pour lemon juice over the chicken.
Bake for 45 minutes, or until internal temperature of chicken reaches 165F.
Remove from oven and let stand few minutes.