Add the black beans, garlic cloves, cumin, chili powder, lime juice, and salt to a food processor. Blend until the mixture is smooth and creamy.

Spoon the blended dip into a shallow serving bowl and spread it into an even layer.

Place the sour cream in a zip-top bag and snip off one corner to create a small opening. Pipe four or five concentric circles on top of the dip.

Use a knife or toothpick to drag lines from the center outward through the circles, forming a spiderweb pattern.

Arrange tortilla chips around the bowl for serving.