Rinse the chickpeas and put in a pot. Cover with water, stir in about 1 Tbsp baking soda, and let soak several hours, or overnight. Try to change the water at least once during this time, rinsing the chickpeas and adding more baking soda. The baking soda will help to soften the water and reduce gassy effects.
When the chickpeas have about doubled in size, change the water and bring the chickpeas to a boil. Turn down to low and cook for 1 to 1.5 hours, or until soft.
Reserve 1/2 cup of cooking liquid. Drain and rinse the chickpeas and put them into a blender or food processor.
Add 1/4 cup cooking liquid, lemon juice, cumin, salt, olive oil, garlic, and tahini to the blender. Blend until smooth, adding more liquid if necessary.
Taste, and add additional ingredients as desired. Keep hummus in the refrigerator, or freeze for later use.
For a garden hummus, add fresh herbs like parsley or cilantro. For a spicy hummus, add red pepper flakes, chili powder, or cayenne.