In a non-reactive pan or plastic storage bag, combine all marinade ingredients with the quail and let marinate for three hours. Remove quail from the marinade, brush off the solids and season lightly with olive oil, salt and pepper. Prepare grill to medium high heat and grill quail to medium (approximately four minutes on each side). Remove to a clean plate and chill.
To prepare the vinaigrette, combine pear-infused vinegar, lemon juice and saffron threads in a small, non-reactive bowl and allow to steep for 15 minutes. Film a heavy bottom sauté pan with one tablespoon of the grapeseed oil. Season the pear with the salt and pepper and sear until caramelized and cooked through. Deglaze the pan with the saffron infused vinegar and remove from the heat. When cool, add contents to a blender. Add honey and tarragon to the vinegar and blend to combine. With the motor running on low, slowly incorporate remaining grapeseed oil and olive oil, season and reserve. This vinaigrette can be placed in tightly sealed container and stored in the refrigerator for up to one week.
To poach the pears, heat a cast iron pan over medium-high heat, season pear rings on both sides and sear to color. Arrange the slices in a single layer in a high-sided sauté pan. Sprinkle thyme leaves over the pear and cover with the vinaigrette. Bring to a simmer and cook for ten minutes. Turn and continue to cook until pears are easily pierced. Remove the pan from the heat and allow the rings to cool in the vinaigrette.
To plate, remove the cool, poached pears to a wire rack to drain. Slice the quail and reserve. In a small bowl, combine the mizuna, Asian pear, lardons, blossoms and pepitas. Gently toss the greens with three tablespoons of the vinaigrette, strain and reserve. Slice the poached pear rings into segments, toss with pickled mustard seeds and arrange onto plates. Top the pear with the sliced quail and gently arrange the salad over all.