For the pear vinaigrette:
Heat the pear juice on stovetop over medium heat to reduce to 1/4 of its original amount, for 40 minutes, until caramelized. Set aside and let cool.
In a bowl, mix the reduced pear juice, cider vinegar, maple syrup, and Dijon mustard. Slowly add the canola oil whisking constantly. Season the vinaigrette with salt, and pepper, to taste. Add a little more pear juice or water if the vinaigrette is too thick. Set aside.
For the salad:
In a pan, add the olive oil and toast the pine nuts on medium-high heat. Keep an eye on them because they tend to burn fast.
Place the endives and grapes in a bowl, add the vinaigrette and mix well. Transfer the salad mixture in the serving bowls and garnish with pears, pine nuts and cheese.