A hearty and flavorful black bean soup with a medley of vegetables, perfect for a cozy meal.
Chop the onion, garlic, celery, and red bell pepper into small pieces.
Uniformly chopping the vegetables ensures even cooking.
In a large pot, combine the chopped vegetables and sauté for a few minutes until they soften.
Stir frequently to prevent the vegetables from sticking to the pot.
Add the vegetable bouillon cubes and boiling water to the pot, stirring to dissolve the bouillon.
Ensure the bouillon cubes are fully dissolved for a consistent flavor.
Add half of the black beans, salt, and cumin to the pot and let it simmer for 5 minutes.
Simmering allows the flavors to meld together.
Use an immersion blender to puree the soup until smooth.
Blend to your preferred consistency, leaving some chunks if desired.
Add the remaining black beans to the soup and stir well.
Adding whole beans at the end provides texture to the soup.
Mix the cornstarch with a small amount of water to create a slurry, then add it to the soup along with the juice of half a lemon.
Stir continuously to avoid lumps forming from the cornstarch.
Cook the soup for a few more minutes until it thickens slightly.
Keep an eye on the soup to prevent over-thickening.
Serve the soup hot, garnished with fresh herbs or a dollop of sour cream if desired.
Serve with a side of crusty bread for a complete meal.