Most recipes call for double the amount of oil vs citrus. I like twice the citrus to oil. Take a couple of oranges peeled and run through the blender add a dash of salt and as much pepper as you like. (You can always ad more but can never remove). Pour into a bowl and slowly whisk in half or less of the total amount of extra virgin olive oil and a tsp of apple cider vinegar or another vinegar on hand. Add slowly to taste, both vinegar and oil. You can add grated ginger if you wish. Some recipes call for grating some of the orange peel into it but I find lettuce to be bitter enough without this. Not as good as quality blue cheese or French but it is good... If at the end you find the oil content too high just throw another orange in the blender and add it to the mix.