Prepare a blanc: Place the four in a large pot and beat in enough cold water to make a smooth, medium-thick paste. Then beat in 2 quarts of cold water, the lemon juice and the salt. Bring to a boil, lower heat, and simmer for 5 minutes.
Remove hearts from artichokes.
Add the artichoke hearts to the water, bring to boil, the simmer gently until the hearts are just tender when pierced with a knife (about 25-30 minutes). Remove pot from heat and allow the hearts to come to room temperature in the liquid.
Gently fry the bacon slices. Do not cook until crisp. Remove and reserve on paper towels.
Place the mustard in a mixing bowl. Using a whisk, beat in the vinegar. Drop by drop at first, then in a thin stream, beat in the olive oil; the mixture should be medium-thick. Add the garlic, and season vinaigrette to taste with salt and pepper.
Remove warm artichoke hearts from liquid and cut in sixths. Place in large mixing bowl and season with salt and pepper. Cut each bacon slice into 6 pieces and add to bowl. Toss with vinaigrette. Serve on 8 individual plates, sprinkled with chopped parsley.
As a first course: Serve just as in this recipe-preferably on stark white plates for a real bistro effect. As a buffet item: This quantity will provide small portions for about 15 people.