First, start by preparing the base for the fresh tomato sauce (if using). To a blender, add the tomatoes and half a cup of water then blend until smooth. Set aside.
On medium heat in a medium-sized pot, heat the oil for a couple of minutes before adding in your chopped onions. Stir frequently and cook for 2-3 minutes until fragrant.
Add in half of the blended tomatoes and allow to cook for 3-5 minutes until you achieve a rich, red colour, stirring from time to time. Then add in the remainder of the mixture, along with the tomato paste, as well as salt and pepper and maple syrup. Allow to cook for another 3 minutes.
Add the trimmed green beans, followed by enough water to cover. Stir through, and bring to a boil.
Cover and cook on low heat for 15 minutes or until the beans are cooked through but still with a bite. The sauce should have cooked down, but if you'd like it thicker you can cook for a further 5 minutes uncovered on medium heat to reduce.
Turn of the heat and add in the chopped garlic and adjust seasonings as needed. Serve warm over rice or grain of choice.