Combine beans and tomato sauce in a small saucepan; bring to a boil over medium heat, stirring occasionally. Remove from heat.
Mash beans with a potato masher or back of a spoon. Add cheese and chili powder; cook, stirring constantly, until cheese melts.
Serve dip warm with toasted pita chips or fresh vegetables (chips and vegetables not included in analysis).
Tip: If you're on a low-sodium diet, make this spicy dip with no-salt-added beans and serve it with unsalted chips or fresh vegetables.