1. Heat vegetable oil in saucepan over medium-high heat. Add onions and saute until translucent. Add garlic and cook for 3 minutes. Sprinkle in the masa harina and stir constantly as it cooks and turns golden.
2. Add the spices and stir for another 2 minutes. Slowly whisk in the warm vegetable stock and bring to a boil. Reduce to a simmer and whisk in the tomato paste and sugar.
3. Simmer partially covered for 30 minutes, stirring regularly. Season to taste.