To prepare the vinaigrette: soak shallots in vinegar for 15 minutes. Whisk in mustard. Add olive oil, salt and fresh ground pepper. Mix well then taste. Adjust seasoning to your taste.
Avocados:
Cut the avocados in half. Remove the pits. Cube them but keep them in their skin. Rub the top with some lime juice to prevent browning. Sprinkle halves with minced shallots and chopped cilantro before dousing them with vinaigrette.
Recipe by Fraiche Pantry at https://www.fraichepantry.com/2014/02/07/avocado-with-shallot-vinaigrette/