Preheat a big stockpot over medium heat. Saute the onions in the olive oil until transparent, 5 to 7 minutes. Add the garlic and cook for another minute. Add the chile powder and mix into the onions. Add the bay leaves, salt, lentils, and 7 cups of water. Mix well. Raise the heat to high, cover, and bring to a boil. Once the soup is boiling, lower the heat to medium-low and let simmer for 30 minutes, stirring every now and then.