Combine all ingredients except olive oil in a blender container. Mix on medium speed until smooth.

With blender running, slowly drizzle in olive oil. To prevent dressing from spattering all over, cover the top of the blender with plastic wrap. Push down on plastic wrap so it droops a bit then place lid on blender with center cap removed. Take a wooden skewer or toothpick and poke several holes in plastic wrap. Slowly drizzle oil through opening in blender cover onto plastic wrap. Oil will seep through the holes. When all oil has been incorporated, remove blender cap and plastic wrap and transfer dressing to a storage container. Taste and season if needed with more salt and freshly ground pepper.