Heat olive oil in a nonstick skillet over medium-high heat.

Add diced onions to the skillet.

Saute the onions for 5 minutes, or until they begin to brown.

Add raspberry vinegar to the skillet with the onions.

Bring the mixture to a boil.

Cook for 2 minutes, or until the vinegar evaporates.

Remove from heat and cool to room temperature.

Drain the canned chickpeas, reserving 1/4 cup of the liquid.

Place the drained chickpeas and chopped fresh cilantro in a food processor.

Process the mixture until it resembles a coarse meal.

Add the onion mixture, reserved chickpea liquid, ground cumin, black pepper, and salt to the food processor.

Process until the hummus is smooth.

Transfer the hummus to a serving bowl.

Garnish with fresh cilantro sprigs, if desired.

Serve immediately or chill for later.