Nachos with Black Beans and Guacamole

• 8 oz cheddar cheese, cut into pieces

Guacamole

• 2 ½ oz white onions
• 4 oz fresh Roma tomatoes, quartered
• 8 oz avocado, halved (approx. 1 avocado)
• 3 oz green tomatillos, quartered
• 1 oz lime juice
• ½ tsp salt, to taste

Black Beans

• 2 cans black beans, undrained (approx. 29 oz)
• 1 garlic clove, minced
• ¼ tsp ground cumin, to taste
• 1 tsp vegetable shortening
• 18 oz tortilla chips
• 4 tbsp sour cream, to taste, to garnish