Put the canola oil and bacon into a large nonstick skillet and cook over medium heat until crisp. Transfer to a plate, reserving the drippings in the skillet.
While the bacon crisps, whisk together the vinegar, syrup, mustard, thyme and some salt and pepper in a small bowl. Slowly whisk in the oil until emulsified.
Put the Brussels sprouts, apples, onions, cranberries and half of the parsley in a large bowl, and then sprinkle with the lemon juice and season with some salt and pepper. Pour half of the vinaigrette around the sides of the bowl, and gently toss to coat.
Make 3 diagonal cuts in the skin of the salmon, taking care not to cut into the flesh. Heat the bacon fat in the skillet over high heat it until it begins to shimmer. Sprinkle the salmon on both sides with salt and pepper. Cook, skin-side down until golden brown and crispy, about 4 minutes. Turn over and cook to medium doneness, about 2 minutes longer.
Transfer the salmon to a platter, skin-side up. Top each fillet with some more of the remaining vinaigrette, then some salad, a little more vinaigrette and the remaining chopped parsley. Serve immediately.