Cook the Lentils: Place the lentils in a pot with 3 times the amount of water. Bring to a boil, then reduce heat and simmer for 20-25 minutes, or until tender but still firm. Drain well and transfer to a large bowl to cool completely.
Cook the Bacon: In a skillet over medium heat, cook the diced bacon until crispy.
Assemble the Salad: In the large bowl with the cooled lentils, add the bacon, sliced pears, crumbled blue cheese, spinach, and chopped radicchio.
Prepare the Dressing: In a small bowl, whisk together the Dijon mustard, honey, cider vinegar, olive oil, salt, and pepper until emulsified.
Combine and Serve: Pour the dressing over the salad and gently toss. Top with toasted walnuts. Adjust seasoning if needed. Serve and enjoy!
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