In a large skillet add in the extra virgin olive oil and bring to a high heat. Next, add in the onions and sauté for 3 minutes, mixing occasionally.
Next, add in the zucchini, salt, ground black pepper, and garlic powder and sauté for 5 minutes, mixing occasionally.
Next, add in the diced tomatoes and great northern beans. Bring to a simmer and cook for 5 minutes, mixing occasionally.
Finally, add in the spinach and cook for 5 minutes, mixing occasionally, or until the spinach is cooked to your liking.
Continue to mix well and cook until the spinach is cooked to desired. The dish should look like this picture.