Put the drained chickpeas and baking soda in a saucepan; cover with several inches of water. Bring to a boil, then simmer 5 minutes until the skins fall off and the chickpeas are falling-apart soft. Drain and rinse.
While the chickpeas cook, process the tahini and lemon juice in a food processor for 2-3 minutes until thick, pale, and fluffy.
Add the garlic, salt, cumin, and olive oil; process 1 minute.
Add the drained chickpeas and process 3-4 minutes, drizzling in ice water 1 tablespoon at a time, until completely smooth and creamy.
Taste and adjust salt and lemon. Serve in a shallow bowl with a swirl, a drizzle of olive oil, paprika, and whole chickpeas.