In a medium sized, nonstick skillet, over medium high heat, heat olive oil.
Add onion and garlic, cook 3 to 5 minutes or until softened.
Transfer mixture to food processor, add beans, chili powder, cumin and pepper. Cover and process until smooth, adding water if
necessary until pureed as desired (sort of smooth is my choice).
Scrape into medium bowl. Fold in chopped marjoram and yogurt.
If you are not serving this dip right away, cover and store in refrigerator.