Prep bread crumbs: Let bread (if frozen) come to room temperature, slice into cubes and toast for 20 minutes (flip half/way) on 350f degrees in the oven on a baking sheet.
Prep chestnuts: Soak chestnuts in hot water for one minute, dry them and then cut a cross on chestnuts. Roast them for 30 minutes on 375f degrees. Peel when cool and chop into small pieces.
Saute bacon pieces until crispy, pull bacon bits out on a plate and set aside, using the bacon fat - cook the chopped onions and celery pieces for 3-4 minutes until soft.
De-stem your fresh herbs, chop them up slightly. Start with 1 Tbsp of each and add to your sauteed veggies.
Add the butter slowly while stirring on low heat, next add the chopped chestnuts. Add another Tbsp of each herb and season with cinnamon, salt, and pepper to taste.
IF YOU'RE PREPPING THIS THE DAY BEFORE: pour this mixture when all soft and well combined after a few minutes over the bread cubes in a baking dish. Cover and refrigerate. The next day before cooking, you can add the egg and broth, stir and bake.
IF YOU'RE MAKING TO EAT DAY OF: Pour mixture over the bread cubes in your baking dish. Beat an egg and add to broth, whisk and pour over your mixture. Stir it a bit and bake for 375f degrees for 30-35 minutes.