Bring chickpeas and 4 cups water to a boil in a 4-qt saucepan. Reduce heat to medium-low and cook, covered, until chickpeas are very tender, approximately 1-1 1/2 hours.
Drain, reserving 1/2 cup cooking liquid. Cool to room temperature. Transfer all but 3/4 cup chickpeas to a food processor and add the tahini, oil, lemon juice, cumin, garlic, chile, and salt. Puree until smooth.
Add reserved cooking liquid and continue to puree until airy in consistency, about 5 minutes. Transfer hummus to a serving dish.
Top with remaining whole chickpeas, drizzle with more oil, and sprinkle with salt.