Shakshuka with Feta

Name: Shakshuka with Feta
Ingredients: 4 to 5 tablespoons olive oil, plus more for drizzling; 1 1/2 medium yellow onions, chopped; Kosher salt and freshly ground black pepper; 4 to 5 cloves garlic, minced; 1 1/2 tablespoons ground cumin; 1 1/2 teaspoons harissa, plus more to taste (different brands vary in spiciness); 1/2 teaspoon smoked paprika; Pinch crushed red pepper flakes; 1 1/2 tablespoons tomato paste; One-and-a-half 28-ounce cans chopped tomatoes; 1 1/2 teaspoons sugar; 8 large eggs; 1 cup crumbled feta cheese; A handful of chopped fresh flat-leaf parsley