In a small pot, heat 2 tbsp of olive oil over medium/high heat. Saute onion and garlic. Once they become translucent, add cumin and toast briefly until fragrant. Then add 1/2 cup of tomato sauce. If you like, you can add a pinch of cayenne pepper. Let simmer until it has a thick consistency. Essentially, you want all the excess liquid to come out of the tomato sauce.