If you choose to use frozen green beans, skip this step. Wash the green beans thoroughly and clean them by cutting the tips of both ends with a sharp knife. Remove the “string” running down the sides, if any. If they are too long, cut them in half.
Place a pot over medium heat. Add the olive oil and let it get hot. Add the onions, potatoes and carrots. Mix with a wooden spoon and sauté for about 6 minutes.
Add the sugar and tomato paste. Sauté for 1 minute.
Turn heat to medium-high and add the green beans. Mix and sauté for about 10 minutes.
Add the grated tomatoes and hot water. Bring to a boil, lower heat to medium and simmer for about 25 minutes, without a lid.
Season with salt and pepper. Add the parsley and more water, if necessary. Simmer for about 10 minutes, until the sauce thickens or until the green beans are as tender or crunchy as you like them.
Remove from heat and add the mint. Allow to cool a little and serve.