French Dressing for Fiona

When ordering a salad you are often asked what dressing you would like to go with it, Italian, French... For some reason the French Dressing served in restaurants outside of France is always some sort of whitish creamy dressing that is all but French, at least not from the France I come from!
When in New York I visited my good friend Fiona and this post is specially for her of "My French Dressing".
The basic rule is quite simple 1/3 vinegar for 2 /3 oil.
I usually make more than I need and store the left over in the fridge. I use an old mustard jar ("Maille" is my favourite choice and can be found easily in the US). The below indications are for a 13.4 oz (380 gr) jar.

My French Dressing
Ingredients
2.5 TBSP Maille Dijon Mustard
2 or 3 pealed and pressed garlic cloves
1 tsp sea salt
1 tsp freshly ground pepper (you can add more according to your taste)
1/3 of the jar Modena Balsamic Vinegar
2/3 of the jar Extra Virgin Olive Oil
When I say 1 or 2/3 of the jar you still need to leave a little space in order to shake properly the mix.
If I have fresh herbs in the garden I also add some (rosemary very finely chopped, thyme, lavender... I leave this up to your imagination and taste)

Method
When all ingredients are in the jar in the order listed above, close tight and shake the hell out of it for 1 or 2 mn, it should become a thick darkish mix, if the oil doesn't mix totally with all add a little mustard and shake again, this time it should be just fine.
Enjoy over a freshly prepared green lettuce.