For the dressing: Place the Roasted Garlic in the pitcher of a small blender or food processor. Add the lemon juice, olive oil, mustard and salt. Puree on medium high until emulsified and smooth.
For the salad: Place the cherry tomatoes, Treviso, fennel and salt in a large bowl. Drizzle with the dressing. Using two wooden spoons, toss well to coat. Sprinkle with the Parmigiano-Reggiano shavings and the crispy capers and serve.
Preheat the oven to 350 degrees F.
Cut the top third off the head of garlic and discard. Place the remaining head in the center of a piece of aluminum foil large enough to wrap around it like a pouch. Drizzle it with the olive oil, sprinkle with the salt and close the edge up around the top, sealing it well. Roast until the garlic is lightly browned and very soft, 45 minutes. Allow to cool slightly before squeezing the garlic from the bottom to the top to remove all the cloves.
To fry the capers, warm 1/2 inch grapeseed oil in a small saucepan over medium heat. When hot, add the capers and fry until opened, golden brown and crispy, about 2 minutes. Using a slotted spoon, remove to a paper towel-lined plate to drain.