Heat a medium dutch oven over medium-high heat and add enough oil to generously coat the bottom
Add the sliced onions and smashed garlic and cook, stirring frequently, until wilted and browned, about 8 minutes
Add the cumin and paprika and cook for 30 seconds
Add the drained black beans and cook, stirring frequently, about 2 minutes
Add the chicken broth and simmer for 10 minutes
Blend the mixture until smooth using an immersion blender
Simmer for about 5 minutes until desired thickness is reached
Season to taste with salt and pepper
Make quesadillas by filling corn tortillas with grated cheese and grilling until melted
Serve the bean soup in bowls topped with sour cream, radish, and avocado
Dunk the quesadillas into the soup and serve
