Cook chopped bacon over medium heat in large, hot skillet on stovetop until nearly crisp.
Add minced shallot and cook with bacon until translucent.
Remove skillet from heat.
Stir in maple syrup, balsamic vinegar, and Dijon mustard.
Blend well.
Stir in oil, and salt and pepper to taste.
In large serving bowl, combine spinach leaves and sliced mushrooms.
Spoon warm bacon dressing over all and toss.
Garnish with soft boiled eggs, red onion slivers and optional additional bacon crumbles.