Instructions

1. 1
   Wrap the bouquet garni ingredients in cheesecloth, and tie with kitchen twine.
2. 2
   Peel and cut the onions in 1-inch wedges, along the grain (look for the lines going from the root to the tip).
3. 3
   Warm the water in a stock pot big enough to fit all the onions.
4. 4
   Melt the butter in the water, and stir to emulsify. Add the onions and stir. Lower the heat to a gentle bubble—the onions should not brown at all.
5. 5
   Add the bouquet garni and cover the pot (a parchment lid works well to keep all the flavors in but let steam escape).
6. 6
   Cook for 2 hours until the onions are soft but not falling apart. If there's too much liquid, turn up the heat a bit near the end to evaporate it.
7. 7
   Remove the bouquet garni, and let cool to room temperature.
8. 8
   Use or store for up to a week in the refrigerator. Drain the liquid before using (it's delicious—you can use it separately).