In a food processor, puree the BLACK BEANS, SERRANO PEPPER, GARLIC, GREEN ONION (white part), CILANTRO, LIME JUICE, GARLIC, CUMIN, SALT, and PEPPER. Add water in small amounts to adjust consistency as needed.
Transfer the black bean dip to an airtight bowl and refrigerate until ready to serve.
To serve black bean dip COLD
Place pureed bean dip in a serving bowl. Sprinkle CORN, BELL PEPPER, COTIJA CHEESE, CILANTRO, and LIME over bean dip. Serve chilled.
To serve black bean dip WARM
Heat the bean dip via microwave or stove, transfer to serving bowl, and add toppings. Serve warm.