Place sliced onions and lemon juice in a small glass bowl, or Ziploc bag. Let sit at room temperature. This will marinade the onions, and make them delicious for the salad.
In a large sauté pan place 1 tablespoon of oil over medium high heat, add green beans and sauté for 4-5 minutes. Add chick peas and another tablespoon of oil and sauté for about 8 minutes until beans are tender. Add garlic, salt, pepper and cook for another minute. Remove from heat, & cool to room temperature.
In a small bowl, pour in the lemon from onions and add the Dijon whisking to combine. While whisking add remaining tablespoon of oil to make a vinaigrette.
In a large bowl combine cooled pea and bean mixture, marinated onions, sliced tomatoes, thawed peas, chopped parsley, chopped mint/basil and vinaigrette dressing. Stir gently to combine and serve at all of your Summer BBQ'S.