In a heavy bottom stockpot (I use an 8 quart), heat olive oil (1/4 cup) over medium heat.
Once shimmering, add chopped leeks (1 cup), chopped into rounds carrots (1 cup) , salt (1 teaspoon) and ground pepper (1/2 teaspoon). Saute until soft (about 8 minutes).
Add the minced garlic (2 tablespoons) and saute for another 1-2 minutes, or until fragrant.
Stir in diced turnips (2 cups) and green beans (2 cups), and saute until the veggies begin to soften (about 5 minutes).
Add vegetable stock (2 Quarts) and diced tomatoes (2 *14.5 Oz Cans) to the pot, and bring the soup to a boil.
Reduce to a simmer, cover, and cook the soup for 30-35 minutes. This can vary depending on your simmer, the heat, and the thickness of your pan -- you'll know your soup is done when the veggies are fork-tender. (It's better to remove them from heat before they get too tender, no one wants soggy veggies in their soup!)
Remove from heat, and stir in the lemon juice, lemon peel, and parsley.
Taste seasoning and add more salt if desired (I always add an additional 2 teaspoons).
Divide into bowls, and enjoy!