Country side dish

For 4 people:
150 g green beans
150 grams of beans yellow
1 onion
150 g carrots
200 grams of potatoes
2 sticks of celery
3 tablespoons olive oil e.v.
salt and pepper to taste.

Wash the green beans and cook for 10 minutes in a pot with boiling salted water; drain and rinse under cold running water; remove any filaments and break them up.
Peel and wash the onion so finely slice; peel and wash the carrots and cut them into sticks, not too thin.
Peel the potatoes and wash them, if they are small whole, otherwise let them cut them in half; wash the celery and remove any filaments, then slice it into sticks.
Heat the oil in a pan, add the onion and sauté, without letting it brown, stir with a wooden spoon and then add the carrots and celery and sauté for 2 minutes.
Place in the saucepan beans and potatoes.
Pour 1/2 glass of water, season with a pinch of salt and cook covered for 15 pieces/20 minutes.
Serve hot on the table in the same pan.