Heat up olive oil in a saute pan, over medium heat. Add onions and garlic and cook for 2-3 minutes, stirring occasionally.
Add water to pan and leave to simmer until about half of the liquid evaporated.
Add spinach, and butter beans, and tomatoes and cook on low-medium heat for 7-10 minutes, stirring occasionally and checking if more liquid is needed.
Season with salt, pepper and optionally za'atar or preferred herbs. Thyme also works great.
Serve with fresh lemon juice to taste.