The very first thing you have to do is, pre-heating your oven at 400 F°.
Now, take a bowl and toss together the butternut squash cubes, extra-virgin olive oil, salt and newly ground black pepper. Grab a medium baking sheet and spread the butternut mixture in an even layer on it.
Place the baking sheet in the pre-heat oven and bake the butternut mixture for just about 30 minutes or until lightly tender, tossing occasionally.
For the meantime, pick a medium bowl and add in the all the dressing ingredients, including balsamic vinegar, mustard, light brown sugar, crushed garlic clove and a pinch of salt. Mix the ingredients until incorporate well and forms a rich Balsamic Vinaigrette. Set the dressing aside until marinate well.
Pick a large serving platter and arrange the drained and rinsed spinach or salad greens on it. Top them with thinly sliced red onion, cranberries, and the chopped walnuts.
Remove the butternut mixture from oven and place them on the top of the ingredients in the platter. Sprinkle blue cheese all over the top of the warm squash.
Now, drizzle in the Balsamic Vinaigrette Dressing and toss gently for 2 to 3 seconds in order to coat the ingredients.
Serve while the Butternut, Blue Cheese and Walnut Salad is still warm.