Wash and trim the ends of the green beans.

Heat the olive oil in a large pan or fry over medium heat.

Add the onions and brown until they start to become translucent for about 3 minutes; then add the garlic.

Cook the garlic until it becomes fragrant, about 30 seconds, then add the chopped peeled tomato.

Cook for about 5 minutes, stirring often to avoid burning.

Then, add the beans and diced potatoes and mix in the mixture;

then gradually add the vegetable stock,

add the salt and pepper.

Mix everything to incorporate it.

If the mixture is a little dry, add more vegetable broth.

Reduce the heat, cover, and cook the beans and potatoes in the tomato sauce for 15-20 minutes.

The beans should be cooked until they are very tender and not too brothy.