In a small bowl, add all the ingredients for the vinaigrette and mix well. Set aside.
Fry the bacon in a frying pan over medium-low heat until crisp. Set aside.
In large bowl, spread the finely chopped spinach, cherry tomatoes, chopped onions, avocado and bacon.
Pour the vinaigrette over the salad. The vinaigrette will be very thick. If you prefer the vinaigrette to be less thick, you can dilute it by adding a little water.