How to Make It
Warm oil in a large skillet over medium-high heat. Add garlic and sauté until golden, about 2 minutes. Reduce heat to medium, add onion and continue cooking until soft, about 5 minutes.
Add black beans with their liquid. Increase heat to medium-high and bring to a simmer. Reduce heat to low; simmer for 15 to 20 minutes, stirring occasionally, until thickened.
Divide rice and beans among 6 plates. Top with cheese, avocado, tomatoes and cilantro. Season with hot sauce, if desired.