Preheat your oven to 375 F. Using a large skillet or oven safe frying pan (I use a 10 inch cast iron skillet) saute your onions, fennel, leeks, and celery in about 2-3 tbsp of oil or butter. I prefer to use a combination of neutral oil and butter.
As the vegetables soften, add your garlic and continue to saute. After a minute or two, add the vermouth to deglaze the pan. Allow the alcohol to cook off and reduce 2-3 minutes.
Add the herbs to the pan and stir though. Then add the bread cubes and stir to coat everything.
To the herb and vegetable bread cubes, add 1 cup of stock and 3 beaten eggs. Continue to stir the mixture in the pan. Add more stock if the bread looks dry. I would start with 1 cup but continue to add until the bread is almost soggy looking.
Spread everything into one layer and drizzle more oil on top to help with browning.
Bake for 20-25 minutes until the top is brown and the bread on top does not look wet or soggy.
Serve directly from the cooking pan, just be careful with the handle so no one burns themselves. This is delicious left over as well and will keep several days in the fridge.