This has become my very favorite green bean recipe of all time.  Delicious!  Easy to make a lot and even easier to reheat! 

1 pound green beans, ends snapped and cut in half
1 onion, chopped
2-4 tablespoons oil
1-3 cloves garlic (to taste), minced
1 pound tomatoes, chopped
salt and pepper to taste
1/4 teaspoon ground allspice
pinch of sugar or maple syrup

Heat oil in skillet and add onion, sauteeing until translucent.  Add green beans and saute until browning, about 5 to 10 minutes.  Add the rest of the ingredients, bring to boil and simmer until desired tenderness, about 30 minutes.  Enjoy!