Wash the potatoes to remove any dirt or debris. Then slice them into quarters.
Fill a large pot with cold water. Add a dash of salt. Add the diced potatoes while the water is still cold. This ensures that the potatoes cook evenly. Bring the water to a boil. Reduce the heat to a simmer, and cook the potatoes for approximately 10 minutes or until they are easily pierced with a fork.
Drain the potatoes from the water and set them aside.
While the potatoes are cooking, wash and trim the green beans. Bring another pot of salted water to a boil. Once the water comes to a boil, reduce the heat to a simmer. Add the green beans, and cook for two minutes. Immediately transfer them to a bowl of ice water to stop the cooking process. This helps the green beans retain their bright green color.
In a large saute pan, add the diced tomatoes, minced garlic cloves, thyme, rosemary, garlic powder, salt, and black pepper. Stir to combine and cook for about two minutes.
Add the cooked and drained potatoes to the pan with the tomatoes. Gently toss to combine.
Drain the green beans from the ice water, and add them to the pan with the tomatoes and potatoes. Gently toss to combine. Top with olive oil (optional). Cover and cook for 1-2 minutes or until everything is warmed through. Serve immediately.