Preheat oven to 375° F. Put torn bread pieces in a bowl and drizzle with a couple tablespoons of olive oil. Toss with your hands to coat then transfer to a rimmed cookie sheet pan to crisp in the oven, 10–15 minutes should do it. Remove from oven and set aside to cool.
Slice cherry tomatoes in half and place in salad bowl. Add parsley, chives, croutons, and drizzle with shallot vinaigrette, starting with two tablespoons and adding more if you wish. Gently toss, crumble on the feta, give one more gentle toss, and it's ready for serving. Pass the fleur de sel.