Heat the oil in a 4-quart pot over low-medium heat. Add the garlic, onions, scallions, and salt and pepper to taste. Stir to coat the onions with the oil. Cover and cook for 10 minutes, stirring occasionally, until the onions are softened and have released some of their liquids. Stir in the paprika, tomato paste, water, and sugar, mixing well to combine. Cover and continue cooking, stirring occasionally, for an additional 20 minutes, or until the onions are soft. Taste for seasonings.