Drain the chickpeas and add to a small sauce pan with the baking soda. Cover with water and bring to a simmer. Then reduce the heat to medium-low and simmer for 25 minutes.
Drain and add to a food processor or blender (you can do this while still hot, or let them cool a bit).
To the chickpeas, add your garlic, tahini, lemon juice, salt, cumin and a little bit of water (start with less than 1/4 cup and add more as needed).
Blend until smooth. If adding the olive oil, I wait until it's mostly blended, then add the oil to make sure it emulsifies well. Add more water if needed to get to the right consistency, and also taste it to determine if more lemon juice or salt is needed (for me, it usually is).
To serve, I spread the hummus onto a platter or a shallow bowl and top with chicken shawarma and roasted veggies, with a drizzle of olive oil. It's great for dipping and snacks as well.