Preheat oven to 400F and line a small baking pan with a silicone mat.
Add the cheese to centre of the mat and lightly pat it down. Bake for 2 to 4 minutes or until golden and crisp.
Remove from oven and allow to cool before breaking into pieces.
Store any leftover in an airtight container in the refrigerator.
Make the Soup:
Preheat oven to 400F. Place parchment paper on a sheet baking pan.
Wash, trim and slice the leeks lengthwise. I used all of the green and white parts (very little waste).
Lay cut side up on the parchment lined sheet. Add the potatoes, garlic, onion and sprinkle with oil, a little salt and pepper.
Roast vegetables until tender, about 30-40 minutes. Remove from oven and peel skin off onion and garlic, once slightly cooled.
Place all the vegetables and lentils in a large pot and cover with broth. Bring to a light simmer, then use an immersion blender to combine until smooth and creamy. (Normally, I would do this part in the Vitamix, but this was a bigger batch than we typically make. If using your blender, you may need to do two batches).
Stir in freshly grated Parmesan and salt and pepper to taste.
Serve with Parmesan chips and chives and a side of garlic crostini.