In a medium-sized pot, heat the olive oil over medium heat until shimmering. Add the finely diced onion and sauté for approximately 3-4 minutes, or until the onion turns soft and translucent.
Incorporate the minced garlic into the pot and cook for an additional minute, stirring frequently, until the garlic releases its aromatic fragrance.
Add the ground cumin, smoked paprika, and cayenne pepper, stirring continuously for about 30 seconds to toast the spices and enhance their flavors.
Next, stir in the drained black beans and vegetable broth. Increase the heat and bring the mixture to a roaring boil. Once boiling, lower the heat and let it simmer gently for 5-10 minutes.
For a smooth soup, carefully blend the mixture using either a countertop blender or an immersion blender until you achieve your desired consistency. If you prefer a chunkier texture, blend only half of the soup and leave the rest intact.
Mix in the lime juice, then taste and season with salt and pepper to your liking. If the soup is too thick for your preference, gradually add more vegetable broth until you reach your desired consistency.
Ladle the soup into bowls and serve hot, garnished with fresh cilantro and generous slices of avocado for a creamy finish.
Notes
Adjust the cayenne pepper to your preferred spice level.