Using a food processor, chop onion, and garlic , and put into the food processor, and grind it thoroughly. Place sour cream and mayonnaise in a large mixing bowl. Add spices, onion, and garlic and Tabasco Sauce. Pour this into the food processor, and mix until all is light and fluffy.
Allow this to sit overnight in the refrigerator before serving. This is wonderful on both salads and fresh vegetables.