Dry the bread cubes in advance in the oven at 270 F for 5-6 minutes. Set aside.
Preheat the oven to 350 F. Fry the onion, celery and garlic in butter for 5 minutes. Turn the heat to low and stir the vegetables. Place the bread cubes in a bowl, add salt and herbs, as well as fried vegetables.
Pour in the broth in small portions and gently stir the bread cubes so that they are evenly saturated with liquid. If you see that the bread is already quite wet, do not add the remaining broth.
Transfer the homemade stuffing to a baking dish, overlapping the least amount possible and cover with foil or a lid. Bake for half an hour.
Then remove the foil and bake for another 10 minutes until crisped. Remove from oven and leave on a trivet to cool completely before transferring into a freezer bag or jar to store for later. Best if eaten fresh though.