Heat olive oil over a medium heat in a large skillet or sauce pot. Add the onions and sauté for 5 minutes to soften. Add the garlic, oregano, cayenne and cloves and cook another minute. 

Stir in the tomatoes, stock and vinegar. Bring to a boil and then reduce the heat down to a simmer. Let cook 7-10 minutes to thicken the sauce - stir every so often. 

Stir in the chickpeas, spinach and feta. Cover and cook another 2-3 minutes. Season with salt as needed and garnish with red chili flakes and parsley and serve.